Small hands will be drawn to these satisfyingly smooth and tactile natural sorting stones that are large enough to be safe for your youngest learners. In four earthy colors and three different sizes, they invite sorting, stacking and exploration of pattern and sequence. It's a great way for young children to develop early math concepts through exploratory play. Natural Sorting Stones are ideal for sensory play activities but are also durable for use in sand, water and outdoors. Each set includes twelve stones in three different sizes (2 inch, 2.5 inch and 3 inch), and four natural colors.