As mavillan already suggested, just use terminator. It allows to display many terminals in a tiled way. When enabling the broadcasting feature by clicking on the grid icon (top-left) and choosing "Broadcast All", you can enter the very same command simultaneously on each terminal.
Here is an example with the date command broadcasted to a grid of 32 terminals. After opening several terminals, click the grid icon (top-left) and choose "Broadcast All".
