My best resource

It's a bit of board outside the office. Here it is.

Each week I put a new openended question on it-usually related tangentially to topics my students would do in class and also open enough for anyone to get started. I've had simple algebra, some probability, all asked in a way which encourage conversation and logical thinking. So far I've got all the puzzles from a great game I played a few years ago called Perplex city. Currently they have to solve a Petals around the rose problem. A timid year 7 was having an argument with a year 11 about this today about how his rule was wrong because it didn't fit every example. It nearly ended in a fight. Good.

If a student gets it right they get 50p and their picture taken to be put up on the board which they take more pride in than actually winning the 50p. I've had crowds of students around the board arguing passionately about why they're right or wrong. It encourages a huge amount of talk in our corridors

The winners are from years 7-11, from lower to high ability. It's simple, it's cheap, it's fun but above more it's engaging and a real focus point of our department and office. Everyone should try something like this.