Have you watched the whole thing? It's great the whole way through. Honestly, it ended early, but the ending is good enough that I am kind of glad that it didn't go on for seasons and seasons. There's not a bad episode in that bunch and I watch it multiple times a year. A real classic. It ended young, but I really doubt it could have maintaned that level of quality for an extended period.
I'm sure some shitheel will show up to naysay me, but check out Undeclared, too. By some of the same people, with some of the same cast. College campus in the late 90s. Also really good, but more of a comedy. Still has a lot of heart, but it's not Freaks and Geeks, but that's really an unfair expectation. It is a great show in its own right, and I *do* wish that one continued because it was rather sitcom-like.