Hello,
Just a friendly piece of advice: be VERY careful doing this, particularly of other people's children. A lot of rinks don't allow it and if you start adding in external microphones etc you're opening yourself up to problems and accusations, even if your intentions are good.
What exactly do you do with the videos? Most of my younger friends are only allowed to be videoed by their parent, in lessons, for specific purposes.
I say this as someone who has worked in schools, done safeguarding courses and is working towards coaching qualfications.