This download provides students with a fun game format to practice understanding common prefixes and defining words that contain common prefixes. These skills are targeted in the Common Core State Standards ELA L.K.4b and L.2.4b. Thirty word cards are provided; targeted prefixes include pre-, re- and un-. Students will draw a card from a given prefix pile and combine the prefix with the root word drawn. Students will then be required to define the new word based on their knowledge of the meaning of the root word and the prefix. Students risk losing all their cards if they draw a "BOOM" card.