Learning Resources Write-on and Wipe-off Venn Diagramand T-chart Desk Mats Develop higher-order thinking skills using graphic organizers common on standardized tests Encourages deeper comprehension of classroom subjects as students work with markers and manipulatives Set of 30 charts features T-Chart on one side and Venn Diagram on the other Enough double-sided write & wipe mats measures 17"L X 11"H Ages 5+