Abstract: An instructional aid consisting of a plurality of objects useful in teaching and understanding basic concepts of number, addition, subtraction, multiplication and division. Each of the objects in the plurality corresponds to some integer number between one and ten and has a thickness representing the number to which it corresponds. Moreover, each object has a surface having a color or combination of colors representing the prime number or composite number to which it corresponds. The surface having such color or combination of colors has the shape of the Arabic numeral representing the number to which the object corresponds. Alternatively, this surface has the shape of a symmetrical figure with a number of sides equal to the value of the number to which the object corresponds. As a further alternative, this surface consists of a linear composite of unit surfaces, the number of such unit surfaces being equal to the value of the number to which the object corresponds.