I work there...
Um, try it if you wish to...
If I were you I would go to Brean sands (right at the end past the holiday camp bit) there is a much nicer beach there than the main weston one - you can park on the beach, walk out along the headland, it's nice. There, or Sand Bay. Or Burham.
Or go up the coast to Clevedon/Portishead where I grew up. Clevedon ha s a beautiful pier and promenade, Portishead has the lake grounds and an outdoor swimming pool (which may still be open at this point in the season)
If you are in the Bath area (where I used to work) try a place called Claverton Weir which is good for paddling, but might be a bit too cold now. Obviously there are other things such as the Roman Baths, wandering through the shops, the museums etc.
Or come into Bristol -- where I live! There are fountains and things in the centre the children can play in, lots of parks and you can go on boat tours round the docks/ go round the SS Great Britain etc.
If you want to go a bit further afield try going across the Severn into South Wales/ Wye valley - does not take that long to get to. There are castles, a beautiful river, boating, steam engines, Puzzlewood, Clearwell Caves - all sorts!