National Council of Teachers of Mathematics
Nctm: Figure This: Don't Fall In
Have you ever wondered why manhole covers are round? Believe it or not, there is a logical, mathematical reason. See if you can figure it out in this NCTM Math Challenge for Families activity. A one-page activity with suggested life...
Annenberg Foundation
Annenberg Learner: Patterns in Mathematics: Guess My Button
This website gives students an opportunity to sort and classify attributes of a group. The applet responds to each selection made and guides student to the next step.
Maths Challenge
Maths challenge.net: Perimeter Sequence
A "one star" geometry problem that requires finding the visual pattern and applying logic with basic math skills to find the perimeter from the sequence.