No more wild guesses. The Estimation Station is the perfect way to teach your students to make logical mathematical estimates. Simply send this jar home with a student to be filled and counted. Then fill the included proportional scoop and share that number with your class. Students use that information to formulate educated estimations about the number of pieces in the jar. Clearer and easier than home-made jars with hard-to-view contents. Small Parts: Not for < 3 yrs. Grades K+/Ages 5+. Includes 4" plastic cube jar with locking lid and sturdy base and 2" plastic cube scoop. Packed activity guide with a week’s worth of activities, including estimation, counting, place value, comparing and ordering numbers, making predictions,graphing, statistics and mathematical reasoning. Parent letter (in English and Spanish) with instructions on filling and counting the jar’s contents. Teaches estimation and proportionality, fractional lines on jar can also be used to teach volume. Dishwasher safe. Measures 4.75"D x 4.75"W x 8.25"H when assembled.