Within the ENSO-World, a fundamental comprehension of the range of numbers from 0 to 9 can be acquired. Counters and their movements on rods with balls and on the number way propose action-related exploration of this range of numbers.

The Spiral Stairs of Calculation (SSC) are adapted for exploring the structure of numbers from 0 to 19. The principle of "increasing by one" and "decreasing by one" can be experienced playfully through the dealing with the SSC and counters/pieces.

The three Stellanians Ulla, Tella and Hella (in German: Ella, Zella and Hella) are responsible for the accounting system in their world. The Stellanian currency are star coins. In order to display the credit of star coins and enter changes in balance, they jump on their rung ladders up and down. In doing so, they display credit from 0 star coins to 999 star coins.

The Number high-rise consists of ten poles – also called staircases – with a hundred beads each. These are arranged through so called platforms into areas that vary from staircase to staircase in the amount of beads. Within the staircases live wights who can jump from platform to platform. Whenever wights stand on platforms of the same height, they can have a party together. Thus, multiplicative connectedness can be explored with the aid of wight parties.

The Dynamic Labyrinths consist of different bricks by means of which various paths can be built. Assignments for Dynamic Labyrinths range from simple constructions for preschool children to creations of complex calculating machines which can be discussed in primary or secondary schools.