What are some ideas to boost the morale of employees in a retail work environment?

I am a Supervisor at a large chain retail store, but the store itself has only about 30 total employees. Our Store Manager was recently promoted and we have a new Manager who is a bit more strict than the last and morale is quite low, especially among the cashiers who we depend on greatly. Any ideas to boost morale would be greatly appreciated. I am to give my Store Manager my ideas by Thursday Oct. 19th so any help is greatly appreciated. Thanks a lot!