There have already been a few threads on this; the Search function will help you browse.
You can see the ac year calendars here; the fall schedule is
https://www.usna.edu/Academics/Calendars-Events/index.php
It shows “early schedule” on the Wed before Thanksgiving. That means all 5 periods start earlier than usual, finishing before noon, and if things happen the way they have in the past, flights starting at 3 from BWI are doable. Allow a lot more time if trying for DCA or IAD. Return times on Sunday have varied over the years from 6 -10 pm. Whatever it is, planes must land 2 hours prior to that time to allow for delays.
Mid departures for winter break will depend on the exam schedule for the individual. Your mid will have to tell you. As soon as their schedules are set, they will know this. Return from leave (“Reform”) works the same way with scheduled flight times, 2 hour buffer.
Browse all the calendars and links. There is a link for Exam Schedules but notes how mids may access.
Never assume the day classes start is the same day they are expected back.
One of the best gifts you can give your mid is training them on booking travel, and then letting them be responsible for it. It will teach them how to research, plan ahead, comparison shop, trouble shoot, and build up airline miles on their own. It’s a critical skill for military personnel of all rates and ranks. Might as well get started as a mid.