We have TONS of bottle caps thanks to our cook and donations from parents. Since we were running out of places to store them I figured it was time for a sorting activity. I set out different colored paper onto which the children could match the caps. That was all that was needed as the children intuitively 'got' the intended invitation.
The children pointed out that I was missing a few colors so I added black, tan and purple paper as well...
There were only a few 'tricky' colors that did not quite match (like a cap that was an orangish-yellow). But they indeed drove us all nuts because they didn't quite fit in either category.
The end!
I swear I saw someone else post about a project similar to this recently, but a Google search proved fruitless. I want to say it was Teacher Tom? Anyway, we've been collecting bottle caps all year. My parents send me home with baggies. They come in plastic containers from parents. Sometimes I'll find one or two in my work mail box.
To begin, the children rolled a mixture of glue and paint onto a large piece of cardboard. Boy, do they love paint rollers. I think this was actually their favorite part.
Then we gathered all of our bottle caps and set them on:
We noticed a problem right away. The glue and paint caused the cardboard to bow so we had to find heavy things to put on top.
Here is a look at the not-so-final- product:
I say not so final because as soon as I lifted the cardboard the bottle caps began to pop off. No worries. I think we will do this again using a piece of plywood and possibly some wood glue as well.
The end!
The children pointed out that I was missing a few colors so I added black, tan and purple paper as well...
There were only a few 'tricky' colors that did not quite match (like a cap that was an orangish-yellow). But they indeed drove us all nuts because they didn't quite fit in either category. 
