We are doing some work with Y9 school kids - before we go into the school, we want to make sure that the experiments work, so we're doing a few trial runs. The idea of this experiment is that the leaves don't photosynthesise under the foil shapes, so that when you test for starch the next day, there is starch in the areas exposed to light, and none in the dark bits - leaving a paler shape on a dark background.
