We read several books about pizza. Then we created doubles with pizza toppings. This pizza and pizza toppings came from a unit my teammate made on fractions. You can find her K-1 fraction unit here. I modified her activity to make it work with a lesson on doubles. You can download my recording sheet for free here.
We created an anchor chart together as we made doubles using unifix cubes. You can get the anchor chart here.
We made doubles using unifix cubes. Then we wrote equations to go with them.
We made a bridge map to show the relationship between the parts of a double and its whole.