Adding a co-teacher in the class
Is there a way to assigning teacher level to another person in the classroom?
Not yet, sadly, no. That's one of several features that the Duolingo for Schools system doesn't yet have. There's also no way of assigning strengthening a skill, or assigning a homework of golding the tree, or keeping it gold, or earning XP that isn't from endlessly repeating the first lesson of the first skill, etc. There's also a lot of detail about your students use of Duolingo that you won't be able to see.
It's early days for the Duolingo for Schools system, and there's a lot of stuff that a teacher needs that hasn't been implemented yet. Hopefully all those features will appear in time.
I need this functionality as well. I have been doing a temporary block as a language teacher while my school's regular language teacher has been away on long service leave. She comes back soon and will need to take over the classes. I'd like to be able to transfer the classes over to her, but it looks like she'll just have to recreate the classrooms on her own profile and have the students re-join.