Definitely don’t correct incorrect answers. We always want to embrace the reality of people with dementia, aka, go along with their story. A great website that I write for sometimes is Alzheimer’s Reading Room. Is it 24 hour care? Since they are out in the country, I really recommend getting a lock for the door that will ensure Granny doesn’t leave the house unattended.
There are a lot of great activities on the MindStart website. I also recommend my Pinterest page for crafts and other brain games!