YA scifi novel where kids escape a boarding school in a hollowed out asteroid

Question

I read a book (or possibly a series of books) in the UK, probably in the late 80s, that’s stuck with me ever since, and I’d love to know if anyone can identify it.

The basic story revolved around a group of kids (3-4?) that had been put in a (British?) boarding school by their parents while they went off to do something (mining?) in space. The kids somehow managed to piece together a spaceship and blast off to find them.

I’m remembering the spaceship as being an asteroid hollowed out in a spiral shape like a nautilus shell. It had a rocket at the center on one side. There may have been a pictorial diagram in the book too.

Beyond that, I don’t remember much of the rest of the story, although there was definitely a point at which they find an empty ship. There’d been some sort of nuclear accident on it; someone had written “THTH” on the wall, which turned out to mean “too hot to handle”.

Anyone got any ideas?

Answer 1

This sounds a lot like Starstormers, a series of five books by by Nicholas Fisk. It deals with a group of children, Vawn, Ispex, Tsu and Makenzi, who escape from boarding school on Earth by building their own spaceship - the "Starstormer". In the words of a Goodreads review:

four children, stuck on Earth instead of with their parents who are pioneers on a new world, find a meteorite, hollow it out, stick a drive unit into it and blast off after their parents, having Adventures on the way, mainly concerned with the Octopus Emperor, who's out to get them, for some reason.

In the second book, Sunburst, they find an abandoned ship in space, which is indeed labelled "THTH" meaning "too hot to handle", which resulted from some leaking nuclear waste.