Makey, Makey – How it works...(3)

The day after the heavy rains we had an almost full strength in the 6^th grade at Udavi. The previous day only seven children had worked with the MM and it felt like a good exercise in observation and expression to see how these children described what they had seen. Based on their descriptions I asked children to write or draw what they felt had happened.

All the pics from the ones who had not come had a computer (or laptop) connected to a leaf/plant and apparently running Scratch and making a sound. The children in their excitement to describe the plants, sticks, communicating with the computer had not been able to describe the MM. However, in their own drawings the MM was present as a black box.

We had a discussion of what we see and observe and what we understand and interpret. Once I pulled out the MM the children were able to recall most of what they had seen, but they could not talk about what they interpreted as to what happened initially. As I gave them time, one aspect of the MM sending signals to the computer was brought forward as something they had not seen, but interpreted based on the reaction of the computer and the lighting up of the board when we touched something. The other aspect of understanding how the board was able to detect that it had been touched was ambiguous.

We went to the computer lab and I gave a 'magic show' with making the MM board respond or not respond to my touching by saying it before hand. The children were very focused on what my hands were doing and whether I was touching the banana gently or not as gently, etc and did not notice that in the times I wanted the MM to respond I was touching my legs to the floor. Once I explained the trick I was able to lift my foot off the floor and use the wire provided to connect to the board with the same effect. Then I made it further simpler by bypassing everything and directly connecting the ground to one of the trigger points and then talking about how the circuit is being closed even by me.

We then discussed why we don't see the same in real life of connecting a battery with a LED and holding the two ends to light it. This brought forward the sensitivity of the MM to detect even not so good conductors. Then we moved to what we saw the previous day with respect to plastic and wood and that even their resistance can drop when things are wet.

We concluded with what precautions a lineman should take when working on main lines. The kid of clothes that he should wear especially when it rains.

I then did the same session with the 7^th graders and was a little surprised that they were able to give all the signals given by the MM (space, click and four arrow keys). All their pictures highlighted MM and had it in this kind of detail. Thought when describing it in words they also cound not convey the MM. I then realized that since we have been working with scratch were able to understand not only that the MM sent some signals, but had perhaps read the code and noticed the signals.

I could, however, not pull the 'magic trick' on them. Almost immediately one hand went up and then within 10-15 sec three more went up on what I was doing with my foot. The loop closing made sense to the children and they went overboard asking me to use various chains of objects that would close the loop, e.g. touch this banana to the next, then to your keychain and then touch it.

We talked about possible uses of what we could do with a MM. The most common idea is a burglary alarm, but I'm hoping more ideas will come.