One great website I discovered recently is A+ Click Math and Logic Problems. The website contains 2250 interactive mathematics problems from Kindergarten to Grade 12. Each problem has clickable choices and a solution appears if user’s answer is incorrect.
An image from a sample problem in A+Click is shown above. The question asks for the shortest path among A, B, C, and D from the origin to (7,6).
According to the website, A+Click’s database adapts to student ability. To progress to a higher level, the student must answer 5 consecutive problems correctly.