Last week Caleb ordered (with my help) a solar-powered robotic kit off the web. It arrived by courier this morning and there was no way we could wait until after school to open and build it. I considered it an educational experience so we got busy straight away, abandoning all book study until later. We first built the motor and then the solar unit, and from there all the pieces can be interchanged like Lego. We assembled a windmill but as there was no sun it was difficult to test! I plugged in a desk lamp but no results - thought maybe it needed to charge so we left it for a while. It was Caleb who discovered that the light source just needed to be closer, and suddenly we had a working model. So exciting! Caleb later built a puppy, aeroplane and boat.