Erica, Frequent breaks is good, as studies have shown the brain can seriously concentrate on only a few concepts at a time and will begin to lose effectiveness after about 30 minutes. If not able to take a break, we can "chunk", which simply is changing either the way we are presenting material, or changing the topic a little bit, with return to the former method later on (in the same period). These "chunks" of information help keep attention, variety, interest, and may make the class a little bit more enjoyable. Barry Westling