We can't accept under-18s as members of the hackspace as yet, due to there being dangerous equipment and various risks around the place.
That said, we are very keen to outreach to under-18s, and so are considering a 'Junior Hackspace' evening/day where kids are welcome to use the space under supervision. Most of the equipment in our space is similar in style to that found in a woodwork/CDT studio at a school, so with the correct guidance it's not infeasible.
This naturally requires a significant time investment to run regularly, and to ascertain the various legal requirements.
If you are interested in having a resource such as this for your child, and in particular are able to help out with the organisation of it, please get in touch.