Our third years have started their junior cert investigations. The physics version is to compare the insulating ability of different materials.
Seems very basic, in fact too simple to qualify as an investigation at this level.
Until you try it out.
I don’t have third years this year but I walked in to PO’s class to see how he was getting on . They were starting off with a control: Putting 100 ml of water into an uninsulated calorimeter and plotting a cooling curve.
But they ran into problems straight away. It took ages for the water to cool down from a starting temp of 80 degrees. So they are wondering how they will manage when it is insulated.
One student came up with the clever idea of using a set time and noting the temperature drop for different materials.
Others suggested using a smaller volume of water to begin with. So then we had to decide which was the best idea, and more importantly how would we decide which was the best idea.
Test them by experiment – bingo.
Now we were getting into it. Conflicting ideas, not quite getting published in a peer-reviewed journal, but nevertheless good stuff. Next we will look at whether we can carry out valid comparisons, but just arguing over it introduces a personal ownership factor as opposed to just following the traditional cook-book receipe.
Then there is still the issue of making sure ‘amounts’ are equal; equal by volume or equal by mass?
And oh my goodness, what if there is no one right answer?
Their homework was to come up with their own ‘hypothesis’; not which was the best insulating material, but rather which is the best way to test this.
Then the bell went and they reminded us that we wouldn’t see them again until January.
I discussed this with PO last year.
The key is for us teachers to get comfortable with this approach and try to adapt all experiments so that they can be carried out in this manner. There may just be hope for us yet.