Assigning a student to a teacher
You can also use the Relation module to implement this. It depends on how teachers are assigned. Are teachers assigned to students ? or lessons ? based on this you can create a relation using the UI and assign teachers. For displaying information relation module integrates well with views, rules, cck and is very easy to create one.

I also used the module in my project where communities can have objectives and goals. I use the relation module to create relations and use the views to display the connections from the community.

I would also recommend you to watch relation tutorial if you want to learn more about it.