Personalized Distressed Ruler Youth T-Shirt. I am the ruler in distressed text with a ruler replacing the letter L in ruler is a funny gift design for mathematicians and mathh teachers at back to school, birthdays and holidays. Let the good times roll in a durable T-Shirt that takes kids from school to play in an amazing array of colors. 5.0 oz., pre-shrunk 100% cotton. Seamless 1x1 rib collar.