References

http://www.essentialschools.org/resources/122 -- gives a good idea of what the purposes of the high school curriculum system are

Data and References: High school curricula

Curriculum standards for high schools are appalling, even at the national level. 

http://www.educationworld.com/standards/index.shtml

The emphasis in all these standards is "knowledge", "mastery", "recall", rather than synthesis or creativity or discovery or design. The curriculum standards promote memorization, regurgitation, and recall of material rather than creative ways to synthesize it together to form new ideas. 

Data: What do high school graduates do?

Trying to find data about what high school graduates do after graduation, I found the Massachusetts department of education: http://profiles.doe.mass.edu/state_report/plansofhsgrads.aspx

(generated from MATLAB)

Over the entire state, this chart clearly shows that the majority of graduating high school seniors go on to college. In college, arguably the most important characteristic is critical thinking skills.