I agree with recommendations to re-order your visits. BU and Northeastern are a good day’s worth, and taking public transport or asking the schools for parking accommodation for your husband is wise. MIT and Tuft’s are another day’s agenda, and leaving time to get to Tuft’s is key. We stayed at a hotel near the Common on our trip and did a lot of walking and subway riding to get a sense of the city, but I understand that might not be the most feasible option for you.
Driving separately to Worcester makes the most sense, of course, and Residence Inn on Plantation Drive in Worcester was nice and a decent deal when we stayed there last summer.