I bought this toy at a garage sale and didn't realize it needed cartridges. Amazon.com was the only place I could find cartridges. I am thankful to the seller for their product, their dependability and the product quality.

I have bought the Math, Spelling, and Brain Quest units by Turbo Twist and like them all. I have also bought all expanding cartiridges available for each model (put up for future use). The units have volume control and also a place for a headset - which is great!

My daughter has recently discovered them again and has spent quite a bit of time using the math and spelling units. I am fixing to order the Vocabulary unit and the Fun Facts unit now.

The fact that you twist & slam while entering the correct answers is very appealing to my 7 year old. I have also seen my 12 and 14 year old picking them up and play for a bit.

We've been trying for two years to get my very bright daughter to memorize math facts. We tried software; we tried flashcards; we tried bribes. Finally she's reached the age where she HAS to memorize this stuff or the consequences are very serious on math tests and newer math concepts. Out of desperation, I bought Turbo Twister. It was like Magic. The first night she spent 45 minutes on it. She hasn't let up much. I've got her doing 15 minutes before bed each night and it's not even a fight to get her to do it. She loves it.

Guess what? It works. She knows her facts cold. That's allowed her to move much more quickly on math tests and to focus on the mathematics rather than on the computation.

Normally I hate drill and kill software, but clearly the sound /music it plays and physical movement it requires of the user combine to make it attractive and powerful for memorizing. ...at least for my kid..As always,.your mileage may differ.