Here is a short video of Eaton working with patterns.
It was the 3rd time I presented that pattern to Eaton. He made a mistake and he corrected himself. That is an awesome feeling when your baby achieves something you didn't see before.
I bought that set of math pattern from:
I highly recommend this set of manipulative. There are many patterns that a toddler needs to fill out. I started with the easiest one, simple 2 color pattern.
Have a great day!