I went through the program in my county and took every Friday off from work to attend class for the duration. I completed the course which was heavily tied to chemical controls and inputs. One entire week focused on 'turf management'. I graduated and began to do the volunteer hours which required more time off work and was more suited to a retirees schedule. A change in the program administrator resulted in my (and a few other) volunteer records vanishing. I wasn't able to restore my records despite more time off work to meet with the new administration. I finally wrote a letter of concern to the state about the situation and did not receive a reply. Several years later I got an invitation to apply for the Master Gardener program.
All this to say that there are many local garden projects which would value your time and energy and likely accommodate your family schedule. I'd recommend almost anything over the Master Gardener program. Your county may be a wonderful exception but I'd check them out thoroughly before investing time, money and energy. My $.02 cents worth - YMMV
