I have been concentrating on my son’s math education for last two years. During this period, I have found many useful resources that I think every parent should know.
One of them is theGreatCoures.com.
It is a LLC company in Chantily, Virginia. It has been running for past 20 years. Right now, it sells the DVD and CD of many college and some high school courses.
It also supports the online streaming for those courses.
There are lots of better living, health, fitness programs and courses as well.
You can find the high school courses section here.
http://www.thegreatcourses.com/tgc/courses/Recommendations.aspx?ps=902
You can find Algebra I, Geometry, Algebra II, Trigonometry, PreCalculus, Calculus here.
You can find the courses by Topic:
Science & Mathematics
History
Fine Arts & Music
Religion & Theology
Philosophy & Intellectual History
Literature & English Language
Business & Economics
Better Living
Professional
High School
All courses are in 30 minutes lectures formats. For example, the

Algebra I
has 36 lectures, each lecture is around 30 minutes.
It comes with a workbook. You spends another $12-$25 to buy the books of all the teaching script.