3-6-9 game is a simple counting game that can be used in the classroom. Students count in turns from 1-100 (more or less), but have to clap instead of speak whenever they are supposed to say 3, 6, or 9, or any number with 3, 6, or 9 in it (ie, they clap at 16, 29, 43, etc...). The game gets more difficult when the students get into the 30s, 60s, and 90s. In these cases, students have to remember to clap twice in the case of 33, 36, 39, 63, 66, etc...If a student screws up and says a wrong number or claps at the wrong time, then they have to put their head down and cannot participate from the rest of the game. If the class is good enough to make it to 100, you can then reverse and count backwards back to 1, if you have the time.

For more advanced classes, you can have them clap on multiples of 3, 6, and 9. Or you can make them count in ordinal numbers (ie., first, second, third, etc...). You can also try changing the game to 2, 5, 8 or something.