Many schools may be building (or having built) Android and IOS apps for their schools. With some work on BBK-12 part the ability to have a PWA that could be pinned to home screens and offer notifications could be made available to all schools.

Microsoft - https://docs.microsoft.com/en-us/microsoft-edge/progressive-web-apps

Google - https://developers.google.com/web/progressive-web-apps/

Apple - Improving through the IOS 12.x lifecycle

If this feature set was built into the core web service it would enable it for all schools.