Part-time jobs that fit around childcare (Minneapolis)

A grocery chain and a hotel near Minneapolis are hiring part-time staff. This is my first time dealing with any of this. Some roles have a small tuition benefit. Is the schedule really fixed?

Check how they treat part-time staff for benefits. Some add them after a set number of hours.

I worked evenings at a hotel. The hours were steady and the team was friendly, but weekends were busy.