Cuisenaire Rods give students visual confirmation of their hands - on investigations of math concepts, from addition to division to fractions. Rods come in various lengths that can be assigned different numeric values or units of measure. Introductory Set of wooden rods contains 74 rods, tray with lid and Activity Guide. Set includes 22 white, 12 red, 10 light green, six purple, and four each of the yellow, dark green, black, brown, blue and orange rods. Use with 2 - 3 students. WARNING: CHOKING HAZARD - Small parts. Not for children under 3 yrs.