Parental Restrictions and Screen Time

Hi,

We have 1:1 iPad at my school, with managed Apple IDs. Several parents have asked about enabling parental controls and screen time on their iPads. As far as I'm aware, since the pupils have Managed Apple IDs, they can't added to a family group, so therefore cannot have parental controls set up. Am I correct in thinking that? Is there another way around it? Many thanks in advance!

Jo