The ‘mental number line’ theory doesn’t appear to hold up vertically. In A Nutshell When people viewed vertical lines filled ...

Together with graduate and undergraduate students, the project (funded by the Spencer Foundation) investigates the development of space-number mappings in preschool children. The project aims to find ...

Horizontal lines run left to right, parallel to the horizon, with slope 0 and equation y = k. Vertical lines run top to bottom, perpendicular to the horizon, with undefined slope and equation x = k.

To mark a value on the number line, eg the number 2, start at zero and take 2 steps to the right. Number lines can also show fractions as values. This number line represents the values between 0 and 1 ...