Personalized I Think Therefore I Teach Toddler Long Sleeve T-Shirt. I Think Therefore I Teach. It takes brains as well as heart to be a teacher. A classic for Fall, Winter and Spring, these long sleeve toddler t-shirts are sure to be a staple in your child's wardrobe. Whether layered or alone, this t-shirt is soft yet durable enough to stand up to your toddler's playtime demands.