Here are some great sites for reinforcing math facts and concepts at home.
Super Kids: This site contains extra practice for many areas of math including addition, subtraction, multiplication, division, fractions, telling time, exponents, and more. You can create your own worksheets and print them for free.
A Plus Math: This web site was developed to help students improve their math skills interactively. It contains online math games, printable worksheets, and flashcards. A unique feature is the homework checker. Your child can input his or her math problem and solution to see if it is correct.
Funbrain: This site has a number of fun online math games that reinforce what your child is learning in school.
Helping Your Child With Math
Teaching Fractions Through Art (Free Printables)
Fun With Math: Hands-On Measurement (Part 1) (Free Printables)
Fun With Math: Hands-On Measurement (Part 2) Paper Airplane and Watermelon Seed Spitting Contests (Free Printables)
High Level Math, Science, and Test Prep Help Online
Increasing Critical Thinking Skills Through Brain Teasers
Free ebook: Fun Math For Young Learners