Agree about bins. I have a proper refractor scope which rarely comes out and is too valuable to take camping. The stars were amazing when I was near Bath recently - even better than any I've seen on my regular trips to northern Scotland.
Another thing is that you see the image upside down in a proper telescope which takes some getting used to. With the bins, your kids can spend some time familiarising themselves quite easily with many things. Plus a monopod is easier to manouvre than a tripod if you want to move around a lot but don't forget to buy an adaptor to attach the bins to it.
And remember that a night with no moon is best. Plus don't bother trying to see any once in a lifetime phenomenons - the UK is always covered in cloud at the critical moment.........
Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.