A story about how the very messy French philosopher, René Descartes, invented an ingenious way to keep track of his possessions. Interest Level: K-3 Reading Level: 3.4 ATOS Book Level: 3.4 AR Interest Level: LG AR Points: .5 AR Quiz: 2464EN Reading Counts Level: 2.8 Reading Counts Points: 2 Lexile Measure: 560 Fountas & Pinnell: P.