This is an exercise I've seen described by a language teacher who uses it with beginners:
Write the numbers you want to teach on flashcards, and distribute them one to each student. Then say them (in order at first), and get the S who has the relevant card to hold it up.
I say 'I've seen in described'; it was at a staff development session, where there were lots of other MFL teachers. Several in the audience objected 'but what if they can't guess?' (there has been no presentation of the numbers beforehand), but the teacher just said 'they always do'. (As an exercise, we tried it with a made-up language, and it worked - although perhaps the sample was a bit skewed!)
I've never had the nerve to try this, but it sounds fun.
- For Teachers