Bill Gates:

he most blunt assessment came from Microsoft chief Bill Gates, who has put more than $700 million into reducing the size of high school classes through the foundation formed by him and his wife, Melinda. He said high schools must be redesigned to prepare every student for college, with classes that are rigorous and relevant to kids and with supportive relationships for children.
“America’s high schools are obsolete,” Gates said. “By obsolete, I don’t just mean that they’re broken, flawed or underfunded, though a case could be made for every one of those points. By obsolete, I mean our high schools _ even when they’re working as designed _ cannot teach all our students what they need to know today.”

I am no fan of Bill Gates. [Slashdot discussion] He does, however raise some useful points, including the biggest obstacle: political will.