The cage looks pretty small and boring for a rabbit. She will out grow the cage, and probably pretty soon. A giant size wire dog crate is a good option as is building an NIC cage. An x-pen is usually a good option, but might not work as well in a class room.
You don't need shavings if you litter train the rabbit. Litter would only need to be in the litter box, and fleece or a towel can be used in the rest of the cage. A cat bed can be good for a nice place to sleep.
Hay doesn't need to be over the whole cage. Many people put hay in the litter box, or have a hay rack above the box to encourage the rabbit to use the box.
Rabbits should have toys and things to play with. Even a cardboard box with hay can work. Hard plastic cat toys can be used as well. Hay or grass ball tend to be popular.
Since class rooms can be noisy and stressful for a rabbit, she should have some where to hide. There are numerous items you can purchase for this, but a cardboard box on it's side can work well too.