A good game to play would be Grammar Gorillas. It has two levels of difficulty: beginner and advanced. All you have to do is click on the correct word. You know which word to choose because it tells you to find the verb, noun, and other grammar words. For example, if it says, "Find the noun," and the sentence was, "She held the umbrella," you would click the noun, umbrella. Find it at http://www.funbrain.com/grammar/index.html.
Another fun game to play would be Math Baseball. The website gives you te problem; then you type in the answer. To lock in the answer, click "Swing". If you got it right, you advance. "Funbrain" (the website) will choose whether you got a single, double, triple, or home run. If you got it incorrect, it's an out. Three outs, and the game is over. You can play with one or two people! It's really fun and a great learning experience! Find it at