Around here, every month a church comes in and holds an early afternoon service of just singing and music and it lasts for about an hour. They also have church each week also. At my grandmother's Assisted Living, they had Bible study every week from a local volunteer.
Nana would get a monthly calendar with the schedule and they'd do things like bingo, movies (w/ popcorn), bowling (which went over big! they'd bowl with those kiddie sets in the hallway), they brought in special singers (some came every month), they made crafts (painting ceramics and making some pretty things they could put in their rooms or give away to as visitor), they'd play games like Skip-bo, rummicube, etc. They had book club, chair massages, fingernails filed and painted.
Since it was AL and the people were mobile, they'd do little trips: movies, shopping, library, special trips like "Dixie Stampede" etc.
I bet they'll have some sort of past info filed that may give you ideas and also what goes over well with the residents at your new place. I will be doing a lady's hair tomorrow who is an AL administrator and I will ask her for some suggestions. She started out as an AD and moved up the ladder and pretty much runs the place.
Oh and at Christmas they always decorate several trees with different themes and then have a contest for "naming the trees". My Nana always won with our help (May she RIP) and she won a certificate for 2 free meals for 2 guests in the dining room which she LOVED.
When they played BINGO etc. for prizes they used to play for hankies and small lotions etc. but soon they changed it and bought things they "needed" and could used: kleenex, socks, stamps,lotions, toothpaste, soaps, candy etc. They keep these items in the "store" and now when you won BINGO, you won some bingo bucks and then you'd take your Bingo bucks to the store and spend them on whatever you wanted. The residents really liked this! The kleenex, for example, was a full-size box and it may cost 5 Bingo bucks.
Good luck with the job!