Give your students a quick and easy assessment on calculating the determinant of a square 4 by 4 matrix. This set of 22 matrices should be printed on card stock, for best use, and laminated. ALl you have to do is give the students the cards and have them silently calculate the determinant. Then, students should quietly line up in order from least to greatest. I usually give leveled prizes to the entire class depending on how many errors exist. It can be used as a warm-up or as a welcome break in a long block period. The accompanying key can be downloaded for free separately.