Visual learning

This morning I read in a Digital Newsletter for German educators ('Der Lehrerfreund') that they now have a section on hands-on examples of technical processes in our everyday environment. Such as 'how does frost create cracks in the asphalt', or 'what happens exactly when you burn sugar'? Great! I thought. German education is discovering the advantages of visual learning, and how digital technology can be used to bring the outside world into the classroom. Filled with anticipation I opened the links, only to find the piece on frost and cracks involving a lot of text and a few graphics which repeated what was said in the written text. If you'd print it, you would have a regular book, as German students have known it since Gutenberg printed his bible. Although it might have been hard to video capture the process of cracks occurring in asphalt because of frost, it should be a piece of cake to do this for the process of burning sugar. My hopes up again, I opened that link, expecting to find some YouTube link showing me tantalising close ups of melting, bubbling and caramelising sugar on a flame. But alas, the Lehrerfreund Techie limits himself to a mere picture:
.
I'm not saying that a graphic is not informative; but why use the Internet and digital technology to explain something you can also find in a regular science book?

Digital technology offers an extended educational value ; it makes learning visual and interactive. There is a sweet video for instance, about a kid who is burning sugar, filmed by his friend. The visual quality of 'the sugar mellting experiment' is not great and while you watch, you keep hoping the kids will not burn down the house in their enthusiasm as aspiring scientists, but the amateur experiment clearly shows you what happens to the sugar. The kids also comment on the smell and mention how it burns ("See, now it starts to burn, and that's black"). We see the sugar melting and caramelising, turning black, but no flame appears. Luckily, the kids turn off the stove afterwards.

This amateur video might actually be a classical learning moment for primary school kids; ask your students to come up with a definition of burning. If you define burning as something catching fire, it seems that sugar needs more than just heat; a catalyst needs to be added to the sugar, as our technical Lehrerfreund has tried to explain to us. What would that look like?

A ten-second search on YouTube yields the following video:

.

It is a German video, from www.netexperimente.de As with any proper German product it is solid, devoid of any sense of humour, and to the point. It starts off with a professional version of what the kids in the kitchen did. There is a bunsen burner, a beautiful cone of sugar (how did they do that?!) and a steady camera. You can imagine the scientist behind the camera, wearing safety goggles and holding his or her breath, as not to disturb the experiment in any way. At first the sugar doesn't catch flame, although it bubbles and turns black; same result as the kids in the kitchen. The follow-up experiment shows the sugar cone covered in ash, which after prolonged burning does catch fire. The video has been sped up for the sake of the impatient YouTube generation - in a matter of a few minutes the white sugarcone turns into a smouldering, flaming towering inferno. Well, not exactly an inferno perhaps; but it does catch fire at some point, because of the ash. Conclusion: sugar needs a catalyst (ash) to burn.

The comments on the video are interesting as well; some students talk of the experiments they did, others comment on it. One doesn't understand the purpose of it, the other one wonders why it didn't catch fire better; one student suggest that perhaps too much ash was used in the experiment. Smart kid. By the way, this was the only German comment; perhaps the smart kid found the solution in his science book...