The November 21st update introduced several new items and mechanics to the school environment:

New disposal conditions were added, including dumping corpses into sewers or using a vat of acid.

Characters now properly switch out of their school uniforms when in town during the daytime on weekends. Technical and Safety Information November 21st Update | Yandere Simulator Development Blog

Several characters received updated hair models, including the leader of the 1980s Martial Arts club and students like Yuna Hina and Sota.

A scythe was added as a usable weapon, located behind the gardening shed.