This set of flash cards contains 32 printable cards on plain paper or card stock and you could laminate them. Each page has cross-hairs for cutting the cards to an exact size and this cuts down on paper usage. You could laminate the entire sheet first, then cut them out or have the students cut them out. This set helps students use the Factor-Label method of unit conversion also known as Dimensional-Analysis. The idea is to get students into groups of 2-4 and have them decide how to create the correct pathways for each quantity. For example converting cm to in: 32 cm x 1 in/2.54 cm = 12.6 in. The students enjoy these activities!