Just to add to the suggestions to start small. The first class I took,at the local high school, the teacher said to buy fabric for the size quilt we wanted. It was an Ohio Star cut out with templates. I needed a queen size so bought, and cut out, the fabric. 10 years later I finally forced myself to finish it. I got so sick of looking at it that it would be put away for extended periods. Techniques weren't very good, points lost etc. Ended up tying it just to get it done. It lives on my bed so all wasn't lost.
I'm sure your grandkids will treasure anything you make.