Rather than the exponential growth of doubling at regular intervals, it seems to be merely a linear expansion. The intervals are not constant.
It looks like this:
1945 (ish): $1214
1955 (ish): $2345, up $1131, or $131.10 per year
1972: $4479, up $2134, or $125.50 per year
2002: $8745, up $4266, or $142.20 per year.
In constant dollars, it's still ugly, but using the "doubling" theme with inconsistent (and actually increasing) intervals seems misleading to me.
Get rid of the federal Dept of Education, and some of these problems start to go away. Neuter the teacher's unions, make it easier to get rid of incorrigible students and inappropriate teachers, and empower the remaining teachers and administrators within their own schools (especially against threats of lawsuits), and many more problems magically disappear.
Sadly, nobody in power will entertain such fantasies.
Better yet - close the government schools and let parents and kids go to the schools of their choice.
Watch the cost of education plummet and the quality to go up exponentially.