Only owner of the Team to start the meeting call

hhbadarin no one here is Microsoft, everyone is giving up their own time and experience, but even Microsoft are just normal folks doing a job.

If you do not want your students creating new meetings you can set a meeting policy for them to prevent all forms of meetings, meet now, outlook, scheduled etc.

If you want to ensure that students can't enter a meeting before the teacher as already shown this is also now possible by setting so that Owners only can enter directly. You need to set this using Skype for Business Powershell, for example to change the Students meeting policy you would

Set-CsTeamsMeetingPolicy -Identity Student -AutoAdmittedUsers OrganizerOnly

Teams does meet the requirements you've explained so far.