MathRacks /Rekenrek Website - Amazing tools to build number sense! Love the magnetic whiteboard ones for whole group lessons.

 Manipulatives:

• Favorite Upper Elementary Manipulatives List (by: Blair Turner)
  

Parent Resources

Helping Your Child Learn Mathematics - Preschool through Grade 5 - English (US Dept. of Education)
Helping Your Child Learn Mathematics - Preschool through Grade 5 - Spanish (US Dept. of Education)