Assessment Prisms-Monsters - Treetop Displays - A useful set of self assessment prisms that comprise of traffic light colour coordinated monsters. Simply fold and glue. Great as a table resource and for real time teaching and learning. Visit our website for more information and for other printable resources by clicking on the provided links. Designed by teachers for Early Years (EYFS), Key Stage 1 (KS1) and Key Stage 2 (KS2).