Update to this thread. Currently using Thinkwell precalculus. It appears to be identical to CTY. Demo is thinkwell and list of topics appears to correspond to the list of lessons in thinkwell. Nothing appears to be added or removed. Though I didn't go through lesson by lesson to compare.
So, my guess is that precalculus Thinkwell is the same as precalculus with trig for CTY. But Algebra 1 does not appear to line up. CTY algebra 1 honors looks to me more like algebra 2 thinkwell-- but I'm not 100 percent sure.
If you go to the cty website
http://cty.jhu.edu/ctyonline/courses/mathematics/algebra_1.html and the Thinkwell website
http://www.thinkwellhomeschool.com/products/algebra-1 you have a side by side comparison of subjects offered (look at the lesson plan for detailed topics)
