This will vary by school. Many schools will have "departmentalized" classes in 4th and 5th, where students may have one teacher for reading and social studies and another for science and math, for example.

My oldest is starting 4th grade and we got a message from DC's homeroom teacher. I think there are other teachers for reading and math but I'm not sure? My child is not in CES but has ELC and compacted math. TIA!