Our nieces and nephews are coming to stay with us for a week at the end of August. We only have one car so we'll be home for the most part until DH gets home from work

Any ideas to keep two 9 year olds (b & g) and one 7 year old boy entertained at home? We do have a big backyard and a pool but I'm not a great swimmer so I'm not comfortable letting them swim often without DH home.

Not much besides a park within walking distance unfortunately!