After promising Maritza she would help her with her class volcano , Sabrina gets late for Witch School , where she gets introduced to a guest speaker in a magic mirror , that favourites Sabrina .
Sabrina is a half - witch .
After promising Maritza she would help her with her class volcano , Sabrina gets late for Witch School , where she gets introduced to a guest speaker in a magic mirror , that favourites Sabrina because she is a half - witch .