The simplest, and one of the most effective, was doing nothing. We had an easily-frightened maths teacher and evryone played up in her classes. The best thing was to smile sweetly and oh-so-innocently at her, row by row, until the whole room was grinning and smiling and she was getting REALLY paranoid. She would spend the whole lesson wondering what we had planned.
The headmaster eventually told us to cut it out and behave ourselves in her classes. But we did like her, it's just that she was a good target. And we never meant any harm by sellotaping the chairlegs to the table.