I think finding a completely online program is tough, but in terms of relatively low residency, Hollins University in Roanoke, Virginia has a strong MFA in Playwriting program (taught there back in 2008 and 2011) for which residency is in the summer, as well as a number of other graduate programs. A number of the students were teachers, as their programs fits well with a teacher's schedule.
RE Colorado Masters – Scott, have you checked into CU Boulder? They have graduate programs in both the Theatre department and the Education department. I also applied at UNC (for doctorate), but my application was deemed "incomplete" because apparently my Master's degree is from a university that isn't 'regionally accredited' and that's against the university's policy, so I don't know if I would have been admitted or not, because my application never reached the decision makers.
I recently moved to CO from WA, and several of my high school students in WA went to Central for their Bachelors, and a Drama teacher colleague did the Master's program there that Krystina mentioned, and I've heard nothing but good things about that school! Also, Western, although I don't know if they have distance learning.
Congrats on your upcoming parenthood!