2s  Double the 1s facts 
3s  Take apart 3 into 1 + 2 
4s  Double the 2s 
5s  Skipcount 
6s 
Double the 3s facts
Triple the 2s facts
Take apart 6 into 1 + 5

7s  Take apart 7 into 2 + 5 
8s 
Double the 4s facts
Quadruple the 2s facts

9s 
Take apart 10 into 1 + 9
Take apart 9 into 4 + 5

12s  Take apart 12 into 2 + 10 