These are some of my favorite math websites. For "Math is Fun," I find it best to type "math is fun" with the concept that you are searching (e.g., "math is fun quadratics").
http://www.mathsisfun.com/links/curriculum-algebra-1.html
http://my.hrw.com (each student has been assigned a user name and password)
https://www.khanacademy.org
http://www.regentsprep.org/Regents/math/ALGEBRA/math-ALGEBRA.htm
http://mathbitsnotebook.com/Algebra1/Algebra1.html
http://www.mathsisfun.com/links/curriculum-algebra-1.html
http://my.hrw.com (each student has been assigned a user name and password)
https://www.khanacademy.org
http://www.regentsprep.org/Regents/math/ALGEBRA/math-ALGEBRA.htm
http://mathbitsnotebook.com/Algebra1/Algebra1.html