Learn it all.

A Hidden Words puzzle aimed at 14- to 16- year olds, containing mathematical words that they should know

Instructions below

[Applet - A hidden words puzzle using mathematical words for 14- to 16-year olds]

There are 30 hidden words in this grid. They are all mathematical words that you should know for GCSE (UK). They appear horizontally - left or right, vertically - up or down, and diagonally - forwards or backwards. All words have four or more letters.
When you see a word, left-click on the first letter of the word, drag the mouse to the end of the word, and then release the mouse button.

If you were right, the letters on the grid will change colour, and the word will appear on the right of the screen. If you weren't right, it could be part of a longer word. For instance, if you see 'ANGLE' and it doesn't work, try 'TRIANGLE' or 'RECTANGLE'.
When you have all 30 words, you haven't quite finished! Look for new instructions at the bottom of the screen.
Keep going until you've found all 30 words. Have fun!