With so many schools running over capacity and many schools splitting large classrooms by partitions one main thought is the partitions will reduce noise but there are other methods also. Partitions for the most part block direct noise and may absorb it but if the ceilings are reflecting noise and the regular walls do not have acoustic wall panels then they may be reflecting noise also. Ceilings can have acoustic ceiling tiles along with acoustic banners and clouds.
Acoustic panels reduce noise by absorbing it and are rated according to how much sound they can absorb. Ceiling Tiles absorb sound and in many cases are made of a cleanable material. Foam is one of the best materials for classroom ceiling tiles.
All of these items come in a variety of styles, colors and material so that you can retain the look and feel of your school without having to resort to an industrial looking school.