Teams for Education: Problem with Privacy

Good evening to you. Loving the prospect of making full use of Teams for Education. However, when students were invited they said that their profiles were visible for the entire community. This news was passed on to me by their teacher. I have gone through the walk-through a few times but some menus in the video and articles do not look similar to mine. I cannot see an option available to make sure that each member is set to be private. I had thought of ticking the ‘under 13’ checkbox for all Teams but even this option is no long available for me to use. I would appreciate some thoughts (or even a lifebelt) from anyone using Teams for Education. Much appreciated.