The sun kept going in and out of the clouds while we were trying to do the experiment. We first tried to burn a green leaf, but we weren't seeing any results. So then I suggested getting one that was already on the ground. Once we held the magnifying glass at the right angle, it didn’t take long before the leaf was smoking.
You can see the 2 little spots in the middle where we burnt the leaf…but then it started raining and we didn’t get to do any more.
So hopefully my kids won't be starting fires this way!