SmartMax is the magnetic discovery concept that enables children, even from a very early age, to experience both the wonders of magnetism and the fascinating world of construction in a safe way.The extra-large pieces make it easy for small children to manipulate them. The magnets have the ideal strength for easy assembly and breakdown of constructions. The outstanding colorfully-illustrated booklets in each set guide you through the basics of magnetic phenomena, show ways to strengthen structures, the steps in building towers and bridges, and carefully present the construction projects in easy to very-difficult sequence. Perhaps most importantly, of course, children thrive on the creative satisfaction of dreaming up their own wonderfully imaginative magnetic assemblies! Smartmax magnets have the correct strength for their purpose and are made from the highest-quality material that can be found. These magnets can carry up to 60 times their own weight! SmartMax bars have a unique color code. "Cold" colored bars (blue, green, and purple) attract "warm" colored bars (red, orange, and yellow) and repel other cold colored bars; warm colored bars repel other warm colored bars. Larger bars have stronger magnets than shorter ones.