The Equal Sign in Kindergarten

I love how math topics just come up naturally in our classroom.  The other day we were doing one of our daily math pages as a warm up to our math time. It was this particular one from my April Morning Math and when we got to the Comparing section we came to 10=10.

There haven't been a lot of these comparing statements that have been equal, so it was a great time to talk about what the equal sign really means.  We talked about how it means the same as, how the answer usually comes after the equal sign, but sometimes not.  Then, a teachable moment arrived.  I gave them an equation: 2 + 3 = 1 + 4.  "Hmmm," I said to them, "What do we think about this?"  I had them turn to a partner and talk about it.  We've never done anything like this before, so there was no telling where we were going with this one.  Right away, when we began to share, one of my smarties said, "It's true.  Take the 4 apart and give 1 to the 1.  That makes 2.  Then you have 3 left out of the 4 and then it's 2+3 on the right side too. So that means it is the same."  Wow!  Someone else said that they could just get an answer from both sides- since 5 was the answer on both sides, it was true.  We tried a few more along the same lines and more of them began to get an idea of what to do.  I know that Kindergarten doesn't have a CCSS about the equal sign, but here's the 1st grade standards.
1.OA.D.7 Understand the meaning of the equal sign, and determine if equations involving addition and subtraction are true or false. For example, which of the following equations are true and which are false? 6 = 6, 7 = 8 – 1, 5 + 2 = 2 + 5, 4 + 1 = 5 + 2.
I guess I am a little ahead of the game, but when those moments come up, you just can't let them pass by. We did another one today and here's what we did.  I love that my smarties are beginning to compensate without me even teaching the strategy!!!  Of course, we had to name it and refer to it by name every time someone uses it in the near future.  Can't wait to see what they can do next- I think I will give them equations with one addend missing on one side like this:  3+4 = ? + 2.