Launching Next has discovered 7 mathematic startups.
My Kid's Numbers & Math
Math Game for Preschool, Kindergarten and little Kids
SIAM: Society for Industrial and Applied Mathematics
former Bell Labs Computing and Mathematical Sciences Research
American Mathematical Society
Wolfram Research: Mathematica, Technical and Scientific Software
Wolfram Research, makers of Mathematica, the only fully integrated technical computing software
Mathematical Association of America
MAA ONLINE--Online newsletter and web site of the Mathematical Association of America
National Council of Teachers of Mathematics
NCTM serves math teachers, math educators, and administrators by providing math resources and professional development opportunities. Working for more and better math for all students.