I think the family probably lives in Alaska. The main character is a boy. The grizzly starts to bother the family, trying to get into the house. At one point, the boy has to go outside when the gizzly may be nearby, to start the generator. In another part of the story, the dad is injured and the boy has to drive for help, although he has never driven before and has trouble with the gears.

I think it must have been a Weekly Reader, although I'm not sure.

Thanks!!