Math Videos are a great way to help enhance learning. It can help to review topics or help with homework. Below are sites that I would recommend for watching helpful math videos:
Khan Academy
Math Playground
Practice problems for various topics to help better understand material
Math Words-Dictionary
Here is a link to a good online textbook
Homework Help:
Ask Dr. Math
Math Dictionary
AAA Math Lessons with practice problems
Timed Multiplication Facts Test
Moby Math Help Videos:
What is a function?
Testing if a relationship is a function
Recognizing Linear Functions
Modeling with linear functions