Over the past few days we have been working on different ways to make the number 10. Here are a few games we have played:
http://www.ictgames.com/save_the_whale_v4.html
http://www.coolmath-games.com/0-number-twins/addition-practice-10.html
Having a strong understanding of the number ten is important for learning to do two digit addition to 100 with regrouping.