Last week we had a crisis at work — we misplaced the key to the Maths Arcade cupboard, in which we store the games (don’t ask!). So I was on the look out for something to do without opening the cupboard — i.e. on pen and paper — and I turned to Twitter for help. What suggestions did I get? What did we do in our Emergency Maths Arcade? Read on.

First, @JamesMoosh suggested challenging the students to open the cupboard, saying this would provide “problem solving, logical/lateral thinking, teamwork” and be a good Maths Arcade activity. One student suggested this too, but backed down when I asked for a guarantee that he could pick the lock shut again afterwards!

Suggestions of games:

- Tic Tac Toe Ten: suggested by @SherriBurroughs, I am aware of this from the blog post Ultimate Tic-Tac-Toe. It’s a kind of mega-Noughts and Crosses.
- Sprouts: suggested by @SherriBurroughs, explained at NRICH. Sprouts was invented by John H. Conway and Michael S. Paterson and popularised in a column by Martin Gardner (who would have been 99 this week).
- Nim: the classic game, suggested by @SherriBurroughs.
- 3D Noughts and Crosses: suggested by @devereuxn. Googling, I’m finding a lot of wooden puzzles and online games, though clearly you could play in ‘3D’ using three Noughts and Crosses boards on a piece of paper and working out the vertical lines between them.
- Straightedge and compass construction golf: suggested by @christianp. I think he may have made this up. He explains that he was thinking of the online game ANCIENT GREEK GEOMETRY, and suggests I “challenge them to construct shapes in the fewest steps”. He calls this ‘golf’ from ‘code golf‘, where you try to write the shortest possible code that implements a certain algorithm.
- Hex: suggested by @relinde. We have Hex in the cupboard, but of course it can be played on pen and paper if you print a grid of hexagons.

All good suggestions, but I needed activities that I was confident running with an uncertain number of attendees. So, what did I take? I took Sprouts, Hex, Chomp and Dots (the latter two from my memory of Nottingham MathsJam and my hasty Wikipedia-ing, respectively). I also took a bag of puzzle bits that are used at open days. It went well, and we had a good time. Next time we hope to open the cupboard, but it’s nice to know that we can pull off an Emergency Maths Arcade if the need arises!

How about maker-breaker games or Hackenbush?

3D Noughts and Crosses, at least on a 3x3x3 board, suffers from a similar problem as the regular version. If played perfectly the person that goes first will always win.