Personalized Biochemistry Cake Toddler T-Shirt. Biochemistry is a piece of cake, unchewable, insoluble cake text with a slices of cake is a funny gift design for back to school. A toddler-soft cotton tee in look-at-me, big kid colors. 4.5 oz., 100% combed ringspun cotton. White is sewn with 100% cotton thread. Topstitched rib crew neck. Double-needle stitched sleeves and bottom hem. Shoulder-to-shoulder taping.