Swipe art is good for older people with limited hand mobility. Put dots of paint on the paper or canvas then let the participant swipe with different tools: small heavy cardboard, sponge, flexible brush, the butt of a closed hand, etc.
Intrigued by string art? Give it a try with this "Home Sweet Home" DIY string art home décor tutorial from Infarrantly Creative.
The couch DIY Heart String Art Project at Vintage Revivals. line a design(heart) with nails on a boars. tie brown (or any color) string to one nail and then wrap all over. it's three dimensional cool.