As different as it looks to you...I really believe the pay off will be BIG!!! We finished up our unit on adding numbers to 20 last week and moved on subtraction. I though you might find it helpful to see one of the kids walk through the process. Thanks Luc for being our model. I will try to do this for the ways we learned to add.
When students have a solid understanding of number concepts they can manipulate numbers. The pay off will be big, when they see that bigger numbers just have more groups of 10!