This activity is designed to help students identify, recognize, and convert within the most common SI units and powers of ten. Students are given a set of 40 cards to be sorted into ten groups of four cards each. Depending on the number of students, they may work in pairs, small groups, or individually. Each group of four cards must have the same quantity – for example, mass, length, or volume. The cards are to be arranged in ascending order, from smallest quantity to greatest. This activity c