Driller is a program designed for children to practice their arithmetic skills, and hopefully give them a fun experience with math.
Driller allows the user to practice all four operations at varying degrees of difficulty. The more challenging levels can be tricky enough for many people, and may help you keep your mental arithmetic fast.
The drills can be untimed for minimal pressure on the math-phobic, or they can be timed in two different modes. In one mode, you have unlimited time to run a certain number of questions, and you can try to reduce your time with each drill. In the alternative count down mode, there is a limited amount of time to finish the drill.
At the end of a drill, your results are presented as the number of correct questions out of the total, the time elapsed or left, and a list of missed questions. The list of missed questions is important for the learning experience.