Personalized Pi Day Funny Math Pie Slice Toddler Full Zip Hooded Jacket. Funny every day is a good day for pie Pi Day Toddler Full Zip Hooded Jacket - Black math shirt. 7.5 oz., 60/40 cotton/polyester. Jersey-lined double-needle hemmed hood. Pouch pockets for all their treasures. Coverstitched shoulders and armholes. Coverstitched rib waistband and cuffs.