The colourful walls are decorated with pentagrams, simple maths strategies and a big green poster of Yoda, the Jedi warrior, with the caption, "May the maths be with you".
Pupils are taking turns to be the teacher by leading their group's activity, while their real teacher, Donna McLean, goes round the room, checking, directing and stimulating thinking.
Being the teacher for a while helps 12-year-old Mark to remember stuff, he says and turns to his group and sets them a stinker. "Right, this is level E. What's 58ths of 2.4?"
If people in a group get stuck, you can help them out, says Robyn, aged 13, before looking at her card to find the next question. "What's minus 1 take away 5?"
More specific knowledge of the 5-14 levels is one benefit of the year spent teaching in the primary schools as part of East Ayrshire's Future Learning and Teaching project, says Ms McLean. It helps pupils' learning "because they know where they are going", she says.
Another is learning how primary teachers use games and activities to make maths fun.
"I do much more of that now. As a secondary teacher you tend to think your kids are too old for games, but it's not true. They love them," she says.