How to add a kind of magic to lessons?
I’ve work as a secondary supply teacher for about 18 months. My tip on creating a kind of magic would be that whatever the subject I'm teaching I try to address the pupils by name. This is hard to do on daily supply as sometimes I get to a school ten minutes before the bell, but most schools will give print outs of registers with pictures and it's easy to memorise some names and faces.
All teenagers want to be valued and made to feel that their efforts are noticed by teacher. Praise and encouragement by name, with eye contact is a valuable tool in teaching respect and creating a caring classroom atmosphere.