I remember a live action show - late 70's early 80's - about children who use a hollowed out asteroid to make a ship. I think they were in a future school and running away to maybe looking for parents. I remember they had a computer they rigged up to fly the asteroid. It’s definitely a UK show.
The set I remember was cave looking with a flat floor and the computer in the middle on the floor with wires leading off. It was very low budget.
I've googled every variation I can think of and gone through the various wiki lists to no avail. I did not find anything close in searches.