The points that other mamas brought us were absolutely right! I was fortunate to find a daycare that is only 1 mile from my work. Of couse, we pay for the convenience, but it worth it! The first couple of weeks, I went to visit at lunch to nurse. After that, I'd go see her once a month and take her "out" for lunch. Also, when they have events (holiday parties, meals, etc) I can actually attend. My biggest complaint is when the baby gets sick. With all the flu scares, any time a child has a fever, they must be picked up immediately and cannot return until they have been fever-free for 24 hours! If my job had on-site childcare, it would ease a lot of the burden of taking off work for parties and events, tneding to her when she's sick, and making the commute much more convenient.
Good luck with your classes!