Roger Chartier(me) is a musician / singer entertainer who has specialized in senior entertainment for a long time.
Having worked with many activity directors over the years, I have gleaned a knowledge of what it takes to entertain a variety of levels of senior audiences as well as handicapped audiences of differing ilk's.
   With guidance from many activity director friends I am the author of several articles on the subject. There are many non-musical entertainment activities as well. You will find some ideas here on the other pages of this website. There are a lot of good ideas for alzheimer's activities, dementia activities, sing-a-longs,
As an example of what an entertainer can do check his web page:
http://www.rogerchartier.com/seniors.html 

You may be interested in this incredibly informative website as well.
www.seniorsentertainer.com