Concrete vs. Abstract Scientific Thinking

This year in Science 9 I wanted the students to be able to perform a task for their final assessment in the electricity unit. Besides all the theory and concepts, I felt that after studying dc circuits the kids should be able to do something with it. Enter the Black Box Test.

The general idea is that each black box has 3 to 4 light bulbs on it with the wires hidden. Students unscrew each bulb to see its effect on the circuit and then use this information to determine the schematic for the circuit.

I don’t think I’m alone when I say that I have a hard time keeping 15 year olds on-task and engaged in science. The students were generally interested in electricity but only up until a point - there’s lots of other things to talk about in class such as sports, girls, movies, girls and even girls. However, the class really got into this assessment. I had kids that were stuck and working hard to get unstuck. No one wanted to quit on any of the boxes. These were puzzles, and puzzles which the kids thought they should be able to figure out.

Eventually students started chatting a bit about the black boxes while working on them. I guess this could be a type of cheating but not in my class. I was right beside them while it was going on, so there was no dishonesty in their actions. They wanted to solve the problem. In many ways this was the perfect assessment because not only was I testing their understanding but they were learning while doing it.

Eventually most kids got most of the circuits (were there four). One circuit in particular confused the kids. Most kids took 10 to 15 minutes for all four black boxes. I sort of figured it was just a hard assessment and the difficulty had to do with the abstract nature of it.

A couple of days later two of my physics 11 students were looking at the boxes. I asked them if they remembered what parallel and series circuits are. We talked for a minute, they were a bit confused but eventually they got it. I then quickly told them about the black boxes and challenged them to find the four circuits. They tried it ou and solved all four in less than two minutes.

Wow. These guys hadn’t touched electricity for two years and they nailed it in two minutes. And while they are good and capable students, I’m pretty sure they were your standard grade 9 male student two years ago.

What was happening? Having read a bit about this kind of stuff, I’d bet a significant amount of money that this is a direct result of brain development and how kids can negotiate between the concrete and abstract. Most of my grade 9 students are still in the concrete stage of scientific understanding while the physics students are working in the abstract. This will probably be confirmed when I do my end of the year Lawson Test of Scientific Reasoning.