In my experience...hot glue guns and senior citizens are not a good match.
Seniors often have very thin skin and that glue is hot, hot, hot. Yikes!
The peanut butter/bird seed/pinecone is a good activity provided no one has a peanut allergy.
Mini heating/cooling pad:
Do your seniors have access to a sewing machine? If so, you can use an inexpensive terry cloth towel cut in half, sew on three sides, turn right side out, fill with regular white rice, sew up the remaining side. You have a heating pad that can be warmed in the microwave to ease aches and pains, or keep it in the freezer for bumps and bruises.
Book mark:
A very simple idea is to get paint sample cards, use the special cut out tool to cut shapes such as trees, holly leaves, etc. Punch one hole at the top; tie a piece of yarn and you have an instant bookmark. Some of the paper punches work like scissors and not all seniors may be able to do that; there are other types that you just need to lean on to make the cutouts -
much easier for those with limited mobility. Here is one example:
https://www.amazon.com/dp/B00C90WMLE/
Edited to add:
For the paint sample bookmark idea, you can also use stamps to add interest. There are tons of examples of these paint sample bookmarks on Google Images so you can see the possibilities.
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