I'm torn on this. On the one hand, I think not taking a required class is sufficient grounds to deny graduation. On the other hand, I think the college was out of line to require "obese"[1] people to take additional classes. The college has a responsibility to prepare students for their adult life, but (a) until I see evidence to the contrary, I highly suspect that special-ed classes for fat people are one of the least effective ways of achieving this goal (b) part of being an adult is taking personal responsibility. I'm not normally someone to whine about nanny government, but the college's policy strikes me as overstepping. My personal moral system also requires more from the students than passively not taking a class for the excuse of 'protesting' to fly, but others may disagree.

[1] Air quotes because BMI should not in any way be considered a reliable way of measuring obesity. Body builders will tend to be considered "obese" because muscle is dense and they have more muscle weight than other people their height.