How Much Lab Time is Enough

Three hours of lab a week?
Four hours of lab a week?
Independent projects with students coming in at night and on weekends?
How much is enough?
[This blog post idea came from John Long, a gifted professor at Vassar College. Thanks, John!]
I remember well my organic chemistry lab while I was a biology major in college. The lab met for four hours a week for the whole semester, which at my college was 14 weeks long.

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