Here is a lesson where we basically play spot the pattern. We start off with base ten blocks and very quickly move to symbols only; however, this lesson does answer a lot of questions with regard to WHY some of the "tricks" with 11's you may have learned work the way they do.
This why we like math, the patterns are easy to see, the rules are consistent, you can prove your answers...but don't get caught up in the rules and theorems. Play and put the children in a place where they can discover the rules for themselves. Once they see the patterns they can often make up their own rules and then test them to see if they always work...if you do it right they will tell you the Pythagorean theorem you don't have to tell them. This is just more of that.
This is a simple lesson just playing with 11's. You could play with 9's (← note those are 1st graders in a classroom) or other numbers just for the fun of it. If the child is curious and having fun the lesson is much easier. We went pretty long considering it was just on 11's but they were fairly well engaged for more than a half hour.
In this lesson they got to practice their addends again, and do some addition and use their counting skills creatively and learn a little about patterns. More fun to be had at Crewton Ramone's House Of Math.
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