Is it GRP?
No makers plate or sail number anywhere?
There were any number of small dinghies sold by boat builders which didn't really have a class behind them.
It may even come from abroad.
There were also many classes which have disappeared.
Do you have all the parts, rig, rudder etc?
What exactly do you want from it?
If the hull is in one piece, it should not be hard to get it sailing using parts from any similar boat.
But the kids might get more out of something more mainstream like a Topper.
Hi, it is a Thames Turtle. I don't think that I ever saw one in the flesh . There are a few references on the net. I don't think it was successful enough to get a class association