http://www.aplusmath.com/cgi-bin/Homework_Helper/mtable (interactive multiplication table)
Math Playground: http://mathplayground.com/
Virtual Manipulatives: http://nlvm.usu.edu/en/NAV/vlibrary.html
Becoming good at estimating isn't just to help you pass the AIMS test! There are lots of reasons that we estimate in real life. Can you think of any? Ask your parents if they ever estimate in their jobs, in taking care of a family, or in other areas of their lives. Are you able to estimate? Do you think you can achieve the highest score on the Estimate! game? Go ahead and try it! It's the same game we've seen in class.
http://www.fi.uu.nl/toepassingen/00062/schatten/welcome_en.html