Hi Special-needs-mom-jh
welcome to the Apple (user-to-user) Community!
Re: is there any way to remove volume control or lock it down from the control center?
Wondering what you have tried so far: In Apple Support's online article for iOS15 (link below):
How to: Use and customize Control Center on iPad - Apple Support
Eg: says:
"Add and organize controls
- Go to Settings > Control Center.
- To add or remove controls, tap or next to a control.
- To rearrange controls, touch next to a control, then drag it to a new position."
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Also says at the bottom of the article: "You can: "Turn off access to Control Center in apps
Go to Settings > Control Center, then turn off Access Within Apps".
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Wondering if you know about Guided Access ...
Seems to be great, if you need to restrict access to one app at a time
Eg: See how to: Use Guided Access on iPad - Apple Support
All the best :-)
PS: Seems you can set a limit for loudness if headphones are worn.
See: Adjust the volume on iPad - Apple Support