Only if you assume labour isn't the prime mover. Assuming that technology improvements help education at all (I'm skeptical -- I learned more about logarithms in math by using an abacus than I did using a calculator), we would ideally want education quality to increase, not decrease. Therefore, we should probably assume costs will stay approximately the same percentage over the years.
One thing I've been thinking about lately is education as related to teacher salaries. In general teacher salaries are pretty poor, but they've always been pretty crappy. However, the civil rights movement has had a big impact since the 50's and there's a big difference. Teaching was and is a female dominated profession -- what's interesting are the opportunities for women since the civil rights act. Now, instead of teaching, the brightest women are more likely to hold more prestigious, higher paying jobs that were previously reserved for white men. In effect, it's as though we were placing a restriction on women that said "If you're smart you can work -- but you can only work as a teacher." I'm not sure how much of a difference this makes, but it seems like it could make quite a bit.