I'm 60-years old and do not have a college degree or any college level math classes behind me. I'm a fairly successful, self-taught, computer programmer working on the edge of big data and data science. The obstacle I face is lack of education and, more specifically, lack of mathematics education.

I took algebra and geometry in high school and trigonometry in the Navy but that was all long ago. I'm looking for online math courses that are free or relatively inexpensive to take to review high-school math and then to take college level algebra, calculus, statistics, and linear algebra.

All I've been able to find are sites with more like math-Cliff-Notes or online university classes that cost 1500 to 2000 dollars per class with tuition and fees. Can anyone recommend good online training classes for high-school and college level math?