This is a great addition to any basic addition unit you are working on. It's a wonderful partner activity, to utlize during math rotations/centers. I touch upon many different components of practicing with basic facts such as: doubles, counting on, +1,+2, etc. This is a nice asset that gets the darlings to go beyond thinking okay "what's ten more?", but onto "what's eleven more?" They can use strategies such as breaking the numbers a part and adding ten, then one more. Either way you approach...it's fun, great practice, and a simple center to use. All you need are number cubes and counters. Copy and laminate, and wah-lah!