1. An educational toy comprising a plurality of different numerical figures, each one having a three-dimensional body defining surfaces at right angles to each other, at least one complete set of said numerical figures presenting the ten different arabic numerals, from 0 to 9 inclusively, the zero and the one being made in both a larger size and a smaller size, the two, the three, the four, the seven, and the eight are made only in said larger size, and the five, the six, and the nine are made only in said smaller size; said numerical figures including a zero of larger size forming the outline of a face, a zero of smaller size representing an eye or a mouth, a two representing the back of the head and connected at right angles to the zero of larger size, a one of larger size, a four and a seven interchangeably connected at right angles to said zero of larger size and each representing a nose, a one of smaller size representing an eye-brow, a three representing a mustache, a five representing an eye, a six representing an ear, an eight representing eye-glasses and a nine representing an ear; each said numerical figure being provided with interconnection means for detachably and interchangeably connecting said figures together, some of said interconnection means being located on at least two of said surfaces of said bodies for interconnecting said bodies at right angles to each other, whereby said numerical figures can be interconnected in different ways to represent a three-dimensional human head having different facial expressions, suggestive of different human emotions.