We started the lesson with a few quick questions on Pythagoras' theorem (I used these ones). I taught them Pythagoras' theorem way back in November, but most of them remembered how to solve the problems with a bit of prompting. I was aiming to refresh identification and use of the word "hypotenuse" and also provide a link from something they'd previously learned about right-angled triangles. After we'd done this, it was on to the first bit of the trigonometry introduction!