If you click on the math-aids link, I believe it takes you to a screen that has a purple monster on it. I think it tries to get you to sign up for a membership. You don’t need to do that. If you hit the back button on your internet browser you should get a different screen. There is a blue tool bar on the left that you can explore. The screen you want looks like the picture below. Sorry, I can’t seem to get it to work any better than that.