What's the Difference Between Division I-A, Division I-AA, Division II, And Division III In college football??

Question

What's the difference???

Answer 1

I think Division 1-A are the biggest schools in college football, while the rest are progressively smaller school and hence, smaller budgets for football,and a smaller fanbase from to draw support, and the quality isn't quite as good. The higher the number, the lower the quality of football and smaller the school, in general. 1-A is better than 1-AA in terms of quality of teams.
D-1" schools are the major collegiate athletic powers, with larger budgets, more elaborate facilities, and higher numbers of athletic scholarships. This level was once called the "University" division of the NCAA in contrast to the "College" division; this terminology was replaced with the current numeric (I, II, III) divisions in 1973. In football only, Division I was further subdivided into Division I-A (the principal football schools) and Division I-AA in 1978. Subsequently the term "Division I-AAA" was added to delineate Division I schools which do not field a football program at all.
Unlike other sports, NCAA college football has a Division 1AA division also. A major realignment came in 1979, when the NCAA established a Division I-AA for schools that have strong over-all athletic programs but aren't among the major football powers. Unlike the Division 1A conferences, these conferences playdown for a championship.

Answer 2

It has to do with the size of the school and the quality of the team. 1-A being the best.