tilting board

[Becky]

a plaything consisting of a board balanced on a fulcrum; the board is ridden up and down by children at either end

[Vania]

A tilting board, also known as a wobble board, balance board or rocking board, is a device used for balance training, physical therapy, athletic training, brain development, and rehabilitation exercises. It typically consists of a flat surface on top of a curved or semi-spherical base, causing the board to tilt and wobble when weight is applied, challenging the users balance and coordination.