That's a great way for kids to learn about responsibility. My 6th grade teacher had a room full of pets. We had a rotating wheel with our names on it to dictate who cared for what pet. Giunea pig, hamsters, gerbils, angel fish, scorpion, or hermit crabs. We also got to take some of the pets home during vacation or summer time. Hope the tank goes well.
If I was a teacher I would have a zoo in my classroom.
I loved it when I was a kid and got to take a hamster or gerbil home for a weekend or christmas break. They can't quite do that with the tank but like you said. It will help teach them responsibility.