I don't think this should be just a matter of study.
It can also be students' paintings, calligraphy and other works, and it can be works of art classes. It would be better if there were paper cuts or origami on it.
In addition, there must be class characteristics.
Also, you can print some colorful words and paste them on them if you can.
It not only has its own characteristics, but also plays a decorative role.