My college biology teacher was a joke. It was his first semester EVER teaching. He looked like a hippy, and smelled like one, too. He was the worst teacher I ever had at college. He'd forget his notes, he'd be difficult to understand any complete thought he attempted to "teach." The only way I passed the tests was to study only from the book for hours, as the notes taken during class were useless....it was almost as if the material covered in class and the tests were from different subjects. I only ended up with an A in the class because I stopped studying at all from my notes, bought an additional biology book and taught myself the subject matter.
Thankfully, I had excellent teachers for my biology and other science based classes. I still had to work my butt off to pull A's in thier classes, but that was because they were very thorough.