Tina Fey inserts her signature humor into the role of Ms. Norbury, while also adding the compassion that we find in all teachers. Ms. Norbury is also the one to remind Cady Heron, played by Lindsay Lohan, that it is more than okay to stay true to yourself. Tina’s character, like many caring teachers and adults, understood that mistakes need to be made in order for you to find out who you really are in life. But the biggest lesson? That fitting in is terribly overrated.