For example, there's an episode in which Howard was trying to prove he was smart enough to attend Sheldon’s class so Sheldon asked him a series of questions to test him.

Couldn't the questions have been answered by a bright high school student. They appeared to have been well below what you’d expect of an MIT graduate. And Howard’s answers were (at least in one case) over-complicated.

I remember hearing that they liked it since it brought science out into the mainstream.