Thumballs are available here.
Luckily they are easy to re-create. I started with a trip into Goodwill. I got 2 small soccer balls for a dollar. On my first ball I wrote categories (weather, vehicles, states, sports, etc.)
I also wanted to make a more generic ball that I could use for articulation. On this ball I wrote letters of the alphabet.
When students catch the ball they read the letter where their thumb lands. Then they look at the Activity Sheet (available on the Thumball website HERE). I have several sheets made for every sound target, so the students get their own sheet.
The students find the letter their thumb landed on and say the words listed, and then use the words in a sentence.
For the older kids, when the novelty has worn off, I give them bingo chips and they cover the letter on the sheet as they land on it. The student who gets them all covered first wins.