Yes, we need to be able to delete Safari History because student regularly select remember me when logging into Schoology and then the next student cannot get in to their account because it retains the previous students log in info.

If there a solution for this yet?

I'm not sure about 'deleting browser history and keeping "content filter"', but when the students select "remember me" you should be able to clear this in the Website Data portion of the Safari settings.
. Amiright?

You could also turn off the Settings->Safari->AutoFill->User Contact Info and Names and Passwords

Good gravy. We are experiencing the same issue with losing the ability to clear Safari cache/cookies, but it appears to be something inside one of our Config Profile - Restrictions. Still trying to narrow it down further, maybe there's something specific to Safari that's killing it.

Yep, we also found out that it is due to the web content filter. Once this is enabled for the iPAds, the Safari history cannot be deleted. Apparently a thought to not be able to clear the history to be tracked by parents or anyone else.