If you need extra help, the only site recommended is Purple Math
. This is a personal favorite of mine as it gives very detailed explanations of most of the topics which are covered at eMathLab. Basically, if you have trouble doing any of my exercises and you would like to see someone else's explanation, this is an excellent resource. Numerous lessons are available in the Lessons Index.
Anyone interested in higher level mathematics, engineering or the sciences, may find the MIT OpenCourseWare site of interest. Students, especially college-bound seniors, are urged to see what a wonderful resource MIT has made available to the public.