That is something not required in a domestic setting, that is what HomeAssistant is designed for. I don't know why your children needs to have access to HA (or the internet afterall).
Some of us in the family are logged into dashboards on our phones with different users, which update depending on which room we are in.
If you want to gate access to certain functionality on a dashboard designed for a common area, you would need to route to a different dashboard upon providing some kind of authorisation, e.g. an onscreen PIN pad.
Happy to discuss.
We didn't know you'd declared this. I hope there are temporary solutions available while your declaration is communicated to everybody else.