The seat is actually a physical therapy exercise/balance cushion. It's made by Isokinetics. They have lots of fun colors! I got the neon orange.
I also have a Birthday Freebie. I wanted to have a card for my students on their special day. I created this printable, and my plan is to have all my students sign the center of the card at the beginning of the year. Then, I just need to run off copies. I will probably only run off a small number of copies at a time, in case I need to add a name for a new student. I'll add the birthday boy/girl's name on the line and sign it before giving it to them. The song at the bottom is to a Christmas tune, but my second graders love it, promise :)
Click on the image for your freebie.