Studio Calico Elementary School Collection - 12 in. x 12 in. Show Your Work Cardstock. This is a double sided 12 in. x 12 in. heavy weight cardstock paper with an olive green background with light blue, yellow and white arithmetic problems, with a variety of different vintage report cards on the other side. This collection coordinates so well together. This is the paper used in the September 2010 "Elementary School" ATC kit. Great paper for school ATCs and other teacher and school related projects and scrapbooks.