April

Have you tried any of the "Science for Seniors" activities? You could look at the website and review the list of themes/topics and adapt your own science activities. The founder of the program's site is http://www.guitarwithgloria.com/sample_science_for_seniors_program.
I am not affiliated at all. I thought it might help though. I am all about adapting my own activities using ideas and samples because a big budget is rare in this field. Hope it helps some!