As I often tell my students, Google is your best friend. If you have a questions or you are stuck on a problem just search on Google and you'll find your answer. Here are some specific sites and resources that may help you with your homework and assignments:
http://www.purplemath.com/ it has examples by topic and step- by- step explanations
http://hotmath.com it has resources in English and Spanish
https://www.ixl.com/ it has practice problems by topics (it includes Language Arts practice as well )
http://hotmath.com it has resources in English and Spanish
https://www.ixl.com/ it has practice problems by topics (it includes Language Arts practice as well )