These printables can be used as an assessment/teaching tool for kindergarten science common core standard K.SPM.a.  This standard says that students should know that matter is found in different colors, textures, and hardness.  These worksheets have students categorize matter by color, texture, and hardness.  I'm working on the Kindergarten Science Common Core organizer now, so if you happen to purchase both you can stick these printables behind this standard in your three ring binder!  :)  Thank you and ENJOY!!!!