Almost all of the extra curriculars that we've tried over the last few years (some for 1 session, some for a term/longer, and some ongoing) seem to expect that the DCs transition to being without a parent in the activity at some stage ranging from about 3yo to when they start Reception.
So for example ballet/dancing and swimming have solo classes at 3, and dancing expects parents not to watch, while we watch swimming classes if we want to/can (I've had periods of a very active DC2 wanting to leap in the pool and the teachers were fine with me taking DC2 out!)
Beavers isn't till 6yo but I'm a Guide leader and I know with Rainbows they expect parents to leave them for most of the first session and thereafter excepting SEN to leave them entirely.
Sunday school ditto - ours expects parents in with them until they start school, we had a slow transition but now our DS who is about to start Y1 manages Sunday School quite well on his own.
DS would ideally prefer one of us to be in all activities with him as he is moderately clingy but a) he behaves better and participates better without us (fairly typical I know!) and b) most of the classes don't want or expect parents to be there either.
However we've been going to a music class which is at a family music centre that has groups for adults too. The youngest groups overlap with my group. I had been working on transitioning DS to attending one of the groups on his own but that group folded due to lack of numbers. I've now asked if he can go into another group but I've been told that is only for parents with children, and parents must participate (that part wouldn't be a problem for me - but I can't attend both!)
Would you typically expect that group music sessions at this age would be for parents AND children? It just seems odd compared to other activities for this age group.
Given he's more likely to mess around if we ARE there, and from my experience with Rainbows this is really common at this age, it seems rather counterproductive to expect parents to be there anyway.
(DH can't take him to the music group because DC2 is too young to attend. DH is also not at all musical, this is "my" thing, and I will at some point want to enrol DC2 as well).