Can you have any influence over what barracks you are based in. I have children and don't want to make them move school.

Hi, in short, yes you can have influence over where you are posted to (you fill in a posting preference proforma) BUT you have join with the mentality of moving around if you join the Regular Army. There are some people that spend much of their career in one place but some people move every 2-3 years and most occasions it means that your children have to move schools. Children's schooling is taken into consideration but the needs of the army come first with family a close 2nd. The army also provide Continuity of Education Allowance (CEA) for those individuals who move but want to maintain continuity of education for their children by putting them into boarding school (only available from Yr 4). It might be that you look at joining the Army Reserves and find a local unit near to you.
Personally, i have 3 children and 1 of my daughters went to 12 nurseries (as i had a number of courses i had to attend and was a single parent at the time) but she ended up going to 1 primary school. My youngest will end up at 3 different primary schools but only had 1 nursery. I use the CEA provision and have 2 of my daughters in boarding school which they started in Yr 7. Children are really resilient and if you're happy they tend to be. Good luck with your decision whatever you end up doing.