Conceptualising Mitosis with Digital Microscopes

The introduction of laptops and digital microscopes into the IB Biology classroom, has offered rich opportunities for students to visualise and research cell structures. In this particular lesson, students were analyzing onion root cells and identifying cells at different stages of cell division or mitosis. The lesson was building and developing on previous understanding and is a transformative example of constructivist learning.

The video showcase below, explains the process and key learning outcomes.

Students were able to use the microscope to analyse the slide, and then capture images of cells at various stages of mitosis. These images were stored on their laptops for further analysis. The students all used simple annotation tools in Preview to highlight the chosen cell and then embedded these images into a table. (see example here) Later that tallied the number of cells they identified at each stage of divison. The process was part of a larger practical research assessment, as part of IB Biology curriculum.

The transformative aspect of this lesson was how the digital microscopes and the laptops enabled the teacher to give critical and timely feedback as students completed the practical. The teacher could look at the magnified image on the screen and help the student identify and classify cells. This is an important aspect of understanding Mitosis as many of the stages are blurry. This style of feedback is more difficult, if only one person can peer down the lens of the microscope at a time. The Motic Digital Microscopes still have the same traditional functionality, different lens etc so that student still acquire and practise the essential practical skills.

Thanks to Cathy Elliott and her lovely Grade 11 Biology class for being part of our showcase.

Dropbox Backup

So I was on boarding duty tonight, and I had a G11 student in meltdown due to lost work, from a system crash - the point is, this student, hard working, intelligent, well organised, had a major misconception of how to use both Dropbox and time machine... SO I asked her, you were working in Dropbox ... right? Wrong. But I tell you what, she will from now on. So I asked around, and all of the students I asked have the same confusion, and then it dawned me ... maybe, just maybe teachers do as well?


The problem is this:

Too many of you don't realise that you should be working in Dropbox, let me say that again.

(deep breath)


You should be working in Dropbox

Too many of you work in Documents or on the desktop (a very naughty habit), and maybe copy stuff into the Dropbox periodically, to backup, or maybe an external hard-drive which of course you don't do enough.

There's no point placing loads of video/photos in there (you can use Time Machine for backing that stuff up) as you probably only have 2GB, well I say 'only' that's 2000 MB, which = about 2000 large Word Documents, so more than enough for you.


So, here's a little video I made, to walk you through this simple little process. It's only 4 minutes and 39 seconds minutes long, but it could well save you a great deal of stress/swearing/time recreating lost work, so it is well worth the investment. Trust me. I know. That's why I have no hair (on my head).

Guidance on Sharing Student Videos

At UWCSEA there will be opportunities where you want to share videos that students in your class have created. As a school we need to think carefully about the intended audience of any video creations and also the content of the video that is shared. These requirements will determine how we share student’s digital work with other students, parents, the wider UWCSEA community and also the general public.

We are in the process of reviewing all the options for sharing video and looking at a long term approach to using public video sharing sites like YouTube, but generally speaking at the moment (Dec 2011) YouTube should not be used by staff for sharing video. The exception to this is for official videos put out by the Communications Department. Alternative methods for sharing video are provided below. Some of the reasons for not using YouTube are provided at the end of this document.

Scenarios	Sharing ideas
A student’s personal video reflection.	Students can upload a video to their personal school Picasa Account and embed this into Mahara. Uploaded as a video file and shared through Google Docs.
A student’s video for a formal assessment	A personal video could be submitted through Studywiz as an assignment to the teacher.
Student’s personal video for peer assessments	Uploaded to a Studywiz Gallery so that other students could comment. Uploaded to a class Picasa Online Album so that others can comment. Linked from Picasa Album into a private class blog. Uploaded and sharing a video file through Google Docs. A Google Doc video inserted into a Google Site page.
Student’s video is shared with parents.	Could upload video to a Picasa Album, and then share a private link via email to parents.
Sharing student work with the UWCSEA community or publicising College events	Some video that are intended for the general public should be embedded within our school website - you can email the Communications Department to discuss how to share the video. Need to check with students and maybe parents informing them on how a video is being shared.
Sharing student work to the general public	Generally student work should not be shared on public forums such as YouTube. We can look at sharing videos for a public guidance through our school Vimeo video account.

Basics of Sharing Video.

Generally you will want to share student work with members of the class and treat the group as a private audience. The easiest way to achieve this is to use a staff Google Account and your online Picasa Album. You can upload any video straight from your iPhoto album on your laptop to your Picasa album. This album is linked to your GApps account. Once you have published the video you can then set the privacy settings and share with students in your class. Here is a short tutorial on sharing video.


Some Issues with YouTube

• Lack of control on comments on videos - many, many comments are inappropriate.
• Links to to inappropriate videos - one or two clicks will get you to inappropriate videos regardless of where you start.
• Lack of general control - we cannot control access or effectively remove videos if necessary
• We have reasonable alternatives available.

Five steps to becoming a Google Docs Ninja

The Google Docs suite has become such an integral part of a teachers toolkit at UWCSEA. Some Grade 12 students would suggest we use it too much :) The guide below might help you use some of the other features available within Google Docs and to tweak your usage. Did you know that you can add comments to a document, or use a form to collect student sign up details? Become a Google Docs Ninja in just five steps.

If you want to go further, and learn more about Google Docs you can visit the Google Apps Education Center and walk through numerous self-guided activities. If you wish to do the tests to become an accredited Google Teacher the school will happily pay the costs. See the Digital Literacy Coaches for more detail.

Download Original

Show me the Learning - IB Chemistry

I have recently been working with Simon Dean and a group of amazing Grade 11 students, on the concept of "Show me the Learning". Simon's initial discussion was around finding a way to truly discover if student's have been able to grasp and to explain concepts in Chemistry. As an Economist's teacher, I am always grappling with this same concept. Students can now effectively plagiarize understanding from books and the internet without really being able to apply conceptual knowledge to the real world.

I believe that technology, is an amazing tool students can use to demonstrate understanding, and for teachers to see and hear how students apply and break down concepts. By using specific tools, teachers can understand some of the students metacognition as they explain an idea. This offers the opportunity for very effective formative feedback.

In Simon's Chemistry class, students had to deconstuct a complex idea into simple language, effectively at level of instruction so that others could understand. This kind of idea of prevalent in a series of videos produced in a Commoncraft Genre. The student were also inspired by the series of RSA Animate presentations that are truly creative. Students had to create a presentation that combined the use of visuals and including an essential oral narration.

The following video is a showcase of the class and a reflection on the technique.

Grade 5 Myth Movies

Andrew Finn has been doing some exciting work with his Grade 5 class.

During term one grade 5 were involved in writing myths as part of their Voice unit. A strong recommendation from the Writing Workshop staff development was that children are given the opportunity to publish and celebrate their writing in a range if diverse formats. 

5AnF spent several lessons in the ICT Lab converting their personal myth stories into movies. 

They began the process by speaking the myth into the iPod touch using the Voice Memo App, which then then emailed to their teacher for reviewing. 

Following feedback, and further editing of their myths, the children then recorded their narration a second time and these were then added directly to their story boards using Adobe Premier Elements on PCs.  Students imported the audio track first, and then edited their video to fit the recording. 

A key focus for the children was to select images and music that held significance for their myth, and to ensure the timing of images correlated with the audio. Cooperative learning was also a large aspect of this work as many students we very capable with the selected software while others were not.

Finally students uploaded their videos to share with each other and comment, via a Picasa web album that their teacher shared with them.

Grade 5 Arts Festival & Keynote

What do you get if you combine, 200 students, 9 teachers, 4 art teachers, 24 Macbooks, over 3 weeks with 1 digital literacy coach? 15 minutes of animated video to use as backdrop for the Grade 5 Voices performance.

Students worked independently to import scans of their own artwork into Keynote. Here they used the Alpha tool to remove the background, and then utlised a variety of animation controls (builds and actions) to create their masterpieces. The final collection of videos were stitched together in iMovie, with an edited score from our dance choreographer to create the final video that was used as the backdrop.

Here a few snippets from the three main sections of the performance.

GoogleSites & ActivInspire in Grade 4

This video showcases one of the many websites created by Grade 4 students for their 'Balance of Nature' unit. Students began the unit by creating a food chain in ActivInspire, duplicating the page, and then editing it to become a food web, from the same biome as the food chains. 

This is a powerful example of 'Assessment for Learning', as students began creating their own section of the Grade 4 Google site at the early stages of this unit, and then with regular formative feedback, developed their site into the final product. 

Students wrapped up the site by taking home an iPod Touch which they used to record an 'Elevator Pitch*' ie, a message communicated in less than 30 seconds, related to the Action element from their chosen line of inquiry. These videos were uploaded to Google Docs, and then inserted into their GoogleSite, using a recently added Google Doc Video feature. 

*Elevator pitch

An elevator pitch (or elevator speech or statement) is a short summary used to quickly and simply define a product, service, or organization and its value proposition. The name "elevator pitch" reflects the idea that it should be possible to deliver the summary in the time span of an elevator ride, or approximately thirty seconds to two minutes.

From Wikipedia, the free encyclopedia

ActivInspire in Grade 5

This short video shows how Grade 5 used the multi-purpose application ActivInspire for the summative assessment in the Where on Earth Unit.

A common assumption with this software is to assume that its sole purpose is for it to be used with an IWB (Interactive White Board) but it is, in actual fact, a very powerful, general purpose piece of software with a magnificent range of uses as a standalone application, running on a PC or Mac.

One very useful way to use this tool is to create a flipchart to use with a class, begin it with class from an IWB, save it to a central location for the students open and continue working on the flipchart on their own.

Show me the Learning

I have been working with a few teachers lately, helping them develop tools to showcase student learning. With MacBooks in the hands of the student they can demonstrate understanding in a variety of creative and innovative ways.

1. Posting or commenting on a blog
2. Creating a Keynote with an oral narration
3. Recording a PodCast of oral recording
4. Creating a CommonCraft Video
5. Through developing a Mahara ePortfolio

Our counterparts at UWCSEA East, recently spent a professional development day exploring this concept. In groups they developed and documented techniques that could showcase learning in the classroom. The products of their work is available below. The resources created are nestled under the headings; Video, Words, Sounds, Images. 

UWCSEA East Show me the Learning

Overtime it would be great to see teachers using a variety of tools in the classroom, to help them discover the level of student comprehension and hence learning. In my opinion tools that allow students to speak, force them to expose their understanding in a way that is not possible in a written format. Traditional formats such as worksheets or essays don't allow students to showcase their work to the same degree. Sometimes it is easy for them to plagiaries ideas from the internet, with the presumption that they understand the material.

Below is a nice simple example of something a Grade 6 Humanities student developed this week. The keynote recording looks at the primary and secondary effects of Tsunamis, by using visuals. A selection of visuals was provided by the teacher Ms McGrath and the finished products were saved into a StudyWiz Gallery. 

The Flipped Classroom and Infographics

Both of the concepts, the Flipped Classroom and Infographics are in vogue at the moment. Hence my choice to share the image below. Infographics are just an informative way of displaying information, you can use Google to search infographics and your subject and you will find a wealth of ideas. Student can also use the infographic idea to showcase their own information. We will try publish some more ideas and inspiration about this later.

An excellent website for infographics is here - http://www.good.is/infographics/

Created by Knewton and Column Five Media

FLIP YOUR VIDEO

Planning a video project? Send your students to Video School! Vimeo, a site created by film makers, has introduced Video School 101.  Video 101 is here to teach you the very basics of making videos and show you how fun it can be.

Vimeo Video School: Video 101

triptico

Triptico is a amazing collection of free teaching tools, currently 23,  for teachers that are meant for use with an interactive whiteboard, (although they could still be used whole class with an LCD projector).

What do you get? The list includes class timers, scoreboards, random student and group generators, word magnet games, quiz tools, spinners and more.

Download it HERE

PDF Guide to Resources

Google Doc Templates

Do you wish you had a Google Doc you could just set up as a template that could then be reused over and over?

Well it's not obvious, but it's not that hard to do either, with a couple of pointers:

First Create the Google Doc that you wish to become the template, or maybe and existing doc, that you wish to empty/edit/adjust to use for a template. When it is ready, save as a Google Doc as you normally would.

Now close the document and view all your Docs, most likely in the Home view. (Click Documents on the Main Menu to get to your Documents Home screen.)


Right click on the document you wish to make into a template and choose 'Submit to template gallery' from near the bottom of the list.

Now you will see a window requesting you to provide some basic information, for people who are wondering if they would like to use your template as well.

Fill in the basics, and then click 'Submit template' at the bottom.

In not too long at all your template will be added to the other templates created by our colleagues at UWC.

How do you use one? Next time you want to create a new Document, choose 'From template' from the bottom of the create list.

There a few other available, if you just want yours, choose 'My Templates' from the tab at the top. It can take a while for a new template to appear in this list, but it will. One day. Soon.

Food for Thought

Using movie tools to support students writing development

This was a workshop presentation I gave recently at the Singapore Teach IT conference. It was based on my teaching experience of using the process of making movies in the classroom with students to help them develop their writing skills. The workshop focused on the pedagogy of setting up writing scaffolds, the process of creating a video then a simple tutorial on using Keynote to create a short video.

More information about the workshop is available here - Teach IT Singapore.

Presentation Tools for Collaboration

This was one of my presentations at the recent Teach IT Conference in Singapore. A presentation about presentations does seem a bit odd. The session focused on ways to encourage a group to work together to create a presentation, then looked at alternative tools such as Prezi and Prezi Meetings to enable more creative and conceptual presentation tools.

More information about the session is available here - Teach IT Conference Workshop

2011 Global Education Conference

We'd like to promote a wonderful professional development opportunity available online, focused on Global Education, for FREE.  It's time for the 2011 Global Education Conference! The conference runs from Tuesday 14th Nov to Friday 18th Nov, with a keynote from Alan November and continues all week with online sessions every hour around the clock.  

This schedule link is in local GMT +8 time.  

To participate, visit the conference Ning and sign-up. Then, you'll log in to the session and the Eluminate utility to participate in the sessions you'd like to see.  

Effective Research with Google

This is a presentation about developing digital research skills in our students. This is something we have been trialling with our Grade 6 students and we have had lots of success. The accompanying poster covers the main points that we should be reinforcing with students when we guide students in completing research in class.

Lizzie Williams as Head of Middle School English has documented her work with some of the Grade 6 classes. She has highlighted the common issues that students face and has suggested some concrete teaching strategies to support you in the classroom. You can read her excellent overview here.

SixthSense technology

Pranav Mistry: The thrilling potential of SixthSense technology

Pranav Mistry demos several tools that help the physical world interact with the world of data including a deep look at his SixthSense device and a new, paradigm-shifting paper "laptop." In an onstage Q&A, Mistry says he'll open-source the software behind SixthSense, to open its possibilities to all.

mind = blown :o)

Using Keynote with Music

Lisa Hill and team have been doing some great things with Keynote. Once the Keynote slides are prepared, students perfomed and were recorded into the Keynote presentation using the File > Record Slideshow feature.

When finished, the completed Slideshow is easily exported as a Short Film/Movie.

Using Google Docs in Writing Workshop

 

This is the first time we've used Google Docs in this way and it was a really big success. The children did the rough draft on paper first of all, one session, and then took that draft into the Google Doc in a following session. Even the act of taking the rough draft onto the Google Docs enabled the students revise, because they didn't just transfer as it was, they were motivated to think about it and make edits even as they transferred it.

We found that the children were more motivated to make larger scale revisions and to more accurately edit through Google Docs. They really enjoyed the commenting feature and this definitely is a tool that enables much more effective teacher feedback including peer feedback with their writing partners. It enables you as a teacher to review their work outside of the lesson as conferring within the lesson with every student can be difficult to manage. These same comments are then the basis for discussions in class afterwards. Overall we found it really beneficial and definitely recommend using Google docs again within writers workshop.

Helen Gamble Literacy Coach - Dover Campus

A future vision of technology

Yes Microsoft is still alive. Perhaps they have been busy making movies like the one below, which describes their future vision for technology. Don't be put off by all the white walls and crazy swiping hand gestures as it is a nice though provoking piece.

New resources - WallWisher

Here are some nice video tutorials on using some newer tools in the classroom. I was forwarded a link from the Scottish Book Trust (random I know...) which has some nice resources and more to come, all presented with a thick Scottish accent for those expat teachers from the UK.

Wallwisher is something I have experimented with in the past and my students have liked it. More recently it has been updated so that students can contribute pictures and also video to the class wall. It can either be collaborative or created purely by the teacher. The video tutorial below contains some nice examples from Art and English I think.

For more ideas: 105 ideas for using WallWhisher in the class.

New Beginnings for Grade 2 students in Digital Literacy

Grade 2 Students make a great start to Digital Literacy in the Primary School

When students start the Junior School they are introduced for the first time to their own individual login, password and personal disk space. There is a lot to learn to be a competent user of I.T. and a good digital citizen. The Grade Two students started the year well and coped extremely well with the challenges they were given.

After the students had confidence in these "housekeeping" skills they went on to make a decision tree using Kidspiration. The next set of the skills the class teachers wanted was for the students to have a strong set of skills using word processing. This included creating documents with good visual appeal and a printed page which highlighted important content and had an appropriate amount of white space on the page. Skills covered included all features of formatting text, borders, inserting clip art and images from a file, printing with appropriate settings and saving documents in a logical organisation of folders with clear easily understood file and folder names.

The next unit of study for the Grade Two students is "How Does Your Garden Grow". Students have planted seeds and are recording the growth of their plants by taking photos on the IPod Touches at time various intervals. They will use these photos to make a video so as the growth of the plant will be speeded up and can been seen by watching the video. After taking their photos the students email them so that they can be saved on the Media Drive and be available for later when they are making their video.

Sorting through the mess...

... that is Google Docs' home page.

It seems like a daunting task. Especially if you have hundreds / thousands of emails.

"Help!" you cry, "Are there ways we can sort through this stuff quickly and as painlessly as possible?"

Yes. There is.

And the solution lies right in front of your eyes. Literally. Scroll down and you'll see it.

Three little tools that will help you manage multiple files.

Actions: Let's take multiple files that you have put a tick next to, and you can choose to Share, Download, Mark as Unread, or remove them from the Home tag (which means they won't show up when you just enter Google Doc's home page) . . . and delete them. Just be careful not to delete resources other people are using in a fit of zealous housekeeping.

The Organize option here will also allow you to move a whole chunk of selected files into specific Collections.

Sort by: has 4 options for us. By default, Google Docs is set to show you whatever has been recently modified. You can now choose to sort according to whether the documents by when they were last opened by you, by title, or by priority. So pick which ever one is most practical for you.

View: List Will show you just a list of documents (this is what you're used to in Google Docs), or you can also set it to View: Details, which will show you columns of who the author is and when it was last modified.

versus

Exploring Cells with the Digital Microscopes

A recent project with our great group of Grade 6 science students focused on using our 14 Digital Microscopes to explore cells. The students spent time learning about cells, preparing slides and understanding how traditional microscopes work. This learning was supported by using the new Science eBook "Exploring Science"

We used the Motic Digital Microscopes to take the students skill development and understanding a step further. Instead of drawing pictures of what they saw down the traditional microscope we could plug the microscopes into the students laptops and they could quickly analyze and compare the different cell structures of animals and plants. This is a nice understanding of transformative learning, where students are using technology to do something that was inconceivable a few years ago and where technology adds value to the teaching and learning.

Lesson Plan - Cell Structures and Digital Microscopes

Reflection

Students remarked how easy it was to plug and the capture images, and they were impressed with the quality of the images. The important step was having the students articulate what they saw to explain the differences in cells. Across the ten different classes this was done slightly differently but students liked the idea of using a simple template and table below.

Teachers were happy with the flow of the lesson and are now confident to help students use the microscopes in class. In the future we need to look a few different things. We could look at purchasing some more digital microscopes so they can be used in different science classes when more students have laptops next year. We could also look at converting some of the traditional microscopes with a digital camera, and how much this would cost. The optics in most of the traditional microscopes are better the Digital Motic Microscopes. As a digital literacy coach I focused on the need for students to do something with the images and to really understand what the images were showing them. Although lots of the draft captured images looked attractive, they actually showed air bubbles, crumpled slides or onion or blurry images at low levels of magnification. The development of student understanding is still so important regardless of how we use the technology in classes.

The video below captures the key moments from a lesson by Carolyn Stannard.

Download Videos from YouTube

Youtube is splendiferous

And what an awesome treasure trove of video delights it is, BUT, not if:

• you don't want to be reliant upon an internet connection to play the video... especially if you have more than one to show...

• you have to wait for it to buffer to play, because loads of people just happen to be online right now.

• you go back to show the video the following week/month/year/decade and it's ...  gone, just gone, or.. what was it called again?

• it has a load of highly appropriate comments (and the punctuation!!!!!????) underneath it, I've seen swearing in comments on a 1970s Mr Happy video, people swear about Mr Happy? (Or use ViewPure)

• you want to be able to insert the video into a presentation, or edit it into a video project... OK this one is a bit more geeky, I'll stop now.

Get my point? You can avoid all of the above by downloading the video in question to your computer, also you can then save it somewhere accessible, lie the shared drive, for you beloved colleagues to use as well.

Nerd Alert

It's really great to freeze frame a scene, (space bar to pause/play) and annotate over the image/scene (note facial expressions that indicate mood, scene details, or maybe situational considerations - oooh look the car is falling) using the IWB 'annotate over desktop' feature, (the blue rectangle with squiggle in it...)


So here's my preferred ways to download youtube video, easy and almost as easy:

Use a website...

1. Find your youtube video, copy the URL in the address bar that's the gobbeldy gook that starts with stuff like 'http://www.youtube.com/watch?v= ... ' stuff in it, see the image below for an example...
2. Copy it
3. Go to a conversion site like keepvid.com, there are others.
4. Paste it in the field (where it says something like 'Enter The Video's URL'
5. Choose FLV or MP4 (I would choose MP4, it's easier to playback, and edit)
6. Click the helpful 'Download!' button

 

Use a FireFox Add-on

Tip - Add-ons are awesome, they are helpful little modifications to your browser that let it do things it can't normally do... like the bionic man.

1. If you haven't already, download and install Firefox - http://www.mozilla.com/en-US/firefox/personal.html
2. Open it
3. Go to Tools > Add-ons
4. Click the 'Get Add-ons' tab
5. Do a search for 'Youtube Download' (there are others, this one I likey) and install it
6. When it's finished you will be prompted to restart your browser.. please do so
7. Go to a youtube video, and Oilah! Now a magical 'Download As' button has appeared below the video, so click it!
8. I would choose MP4 for the aforementioned reasons...
9. That's it, now any time you visit youtube with this browser on this computer you can download with one click.
10. Oh, there's more? Why YES. With this Add-on you can also download the audio ONLY, as an MP3 file, really handy for locating obscure bits of music you need...

You might need to download VLC to play the video with, either way it's well worth it.

http://www.videolan.org/vlc/

size matters...

Do you know your bytes and pixels from your mega/kilo/giga/tera bytes? If not, read on...

Quite a few teachers have approached me, who are worried about using up their hard drive space, but fret not dear educators, your MacBook has a HUGE hard drive - but how huge? Generally when I excitedly point out that you have maybe 200 to 500 Gigabytes of space (depending on the age of your Mac), I invariably get a look that looks like I have just emitted a noxious fume from my nether-parts. So here goes...

The smallest unit of memory is a bit, then a byte, and they go up in thousands from there, so a thousand bytes in a kilobyte, a thousand kilobytes in a megabytes... and so on.

Here's a simpler way to imagine it...

1 bit (short for binary digit) = teeny tiny, the smallest size you can get, and yes, useless to you.

1 byte (b) = 1 character in the alphabet, eg the letter 'a'. = still useless

1 kilobyte (Kb) = 1000 bytes = 1000 characters, eg, a page of text = now we're getting somewhere...

1 megabyte (Mb) = 1000 Kilobytes = 1000 pages of text = 1 large digital image = 1 minute of music (mp3)


5 megabytes = 5,000 kilobytes = 5,000 pages of text = 1 very large digital image = a 5 minute song (mp3) This is pretty much the upper limit for email attachments.

10 Megabytes = 10,000 KB = 10 large photos = 10 minutes of music = 1 minute of video.


1 gigabyte (Gb) = 1000 megabytes (MBs) = an entire film/movie

1 terabyte (Tb) = 1000 GBs = MASSIVE = Pretty much only relevant for storage, external hard-drives etc.

Yes there are more...
...

In a nutshell

bytes - pretty much useless, like a few peas.

kilobytes (KB) like pages of text (text emails and small images would be measured in kilobytes) the most useful size online, not too small not too big.

megabytes, now we're getting heavy - large photos, music, 10 MBs or more for video

Maybe these analogies can help?

Animals:
ant, mouse, dog, elephant, blue whale

Food:
a grain of rice, a bowl of rice, a bag of rice, a sack of rice, a truck load of rice

Travel
a coin, hand bag/back pack, carry on luggage, suitcase, a plane load of luggage

To confuse things, images use more memory than text, and are measured in pixels, which do relate to size, but are not the same thing. Your MacBook Pro screen is at least 1200-1500 pixels wide, so that gives you an idea...

With the kids it can be helpful to get them to think of pixels in similar ways to mm, but this will lead to confusion later as they're actually smaller, but at least it's in the right ballpark. Like the image above looks about 8 cm wide on my screen, but is actually 400 px wide, not 80mm, but because higher resolution screens have smaller pixels you can't just compare using a ruler against the screen, this is obvious to geeks like me, but to normal people this is the kind of essential information that is rarely obvious.

As a rough guide:

• 10 pixels square = tiny, the size of 1 font character, like the letter 'o' = 1kb 
• 100 pixels square = the size of about 4 desktop icons = 10kb 
• 1000 pixels square = small/standard monitor (screen) size = 1 Mb 
• 10,000 pixels square = large or 'high definition' (size of a window), high resolution image/poster = 10 Mb 

So when Googling images, a pixel size of about 500px is ideal, 50px is too small (blurry) and images in the 1000s are probably too big (takes ages to load, and display).