If you could grade the presidential candidates on their education platforms, what would you give them?

Newsweek magazine did just that after getting the opinions of Education Sector’s Thomas Toch and the Center for Education Reform’s Jeanne Allen.

Former Arkansas Gov. Mike Huckabee, a Republican, fares the worst, earning a D+ in part because Arkansas’ academic benchmarks are “the pits,” according to Toch.

Sen. Hillary Rodham Clinton of New York, a Democrat, earns a B- despite “currying favor” with the teachers’ unions (in Allen’s words), although Toch predicts she may embrace the idea of merit pay for teachers if she becomes the nominee.

Sens. Barack Obama of Illinois and John McCain of Arizona tie for best grades, with each getting a B+. Obama, a Democrat, gets points for being “well intentioned” and talking about merit pay.

McCain, a Republican, gets high marks for his pro-charter school and pro-private school voucher stances. But Toch asks an important question regarding McCain’s mention of improving high school graduation rates: “How exactly do you do that?”

Perhaps a more appropriate grade for McCain would be an “I” for incomplete. He’s the candidate who has said the least, so far, about education.