Heating/Reheating Large Quantity of Rice

Wife is a schoolteacher and they are having some sort of cultural exchange thing tomorrow. As such, she has asked me to cook gumbo for approx 50 kids that they will eat for lunch tomorrow as part of a program.

My gumbo takes several hours to cook and I am unable to take time off in the morning to cook it. So my plan is to cook the gumbo this evening, refrigerate overnight, and send it with her to school in the morning along with two large crockpots that can be used to reheat the gumbo. (She is unable to use any stoves, etc in the cafeteria to reheat it, and we can't find anyone that can deliver it to her hot at lunch time).

My issue is the rice. I've never reheated rice before in a large quantity. I don't really like reheating it at all, but if I need to, it's a bowl at a time in a microwave.

Anyone have any good ideas for reheating rice, given the lack of a kitchen to do so? I don't think a crockpot would work, right? And if she reheats it before work, it will probably be cold in the 4-5 hours before lunch.

Thanks in advance!