Ooh, we were in Benodet yesterday! It's lovely.
First, there's a 'train' (really a series of motorised carriages) that does a guided tour (In French and English) of the town. Kids love it.
Drive over to Concarneau or if you are feeling brave, there's a little ferry from Benodet to Concarneau. Might be v choppy in poor weather though. Concarneau has an old walled town, complete with ramparts and a little museum. Plus loads of crêperies and ice cream places and little touristy places, like a traditional clog shop, that the kids will love. My two spend 15 minutes admiring the lifelike stuffed cats and rabbits in the gift shop every time. There's the best kouig aman shop there, too. Unmissable.
Drive over to Quimper. Beautiful ancient city with impressive cathedral and town square. Lots of upmarket shops, expensive clothes, shoes, bags, leathergoods and a great covered Market with lots of high end traiteur stalls. Always good for a wander. There's a nice traditional carousel in the cathedral square which little ones love.
The Aquarium in Brest is world class but an hour's drive so plan it accordingly.
The Market is on Monday in Benodet, always good for a delicious rotisserie chicken and a wander.
We are 10 miles away in Fouesnant. We have guests coming next week and I am really disappointed that after a summer of consistent good weather, next week is going to be endless rain :(