In order to change a Childs pre-order on the whiteboard you will need to have the following enabled in your whiteboard setting: Cypad> Settings> Site Info> Whiteboard> Parent selection can be removed in Whiteboard
Once a meal has been selected you will not be able to change the selection on the whiteboard without first deleting the current pre-order.
To do this: hold down Ctrl and click onto the Childs name on the whiteboard.
A message will then appear asking you to confirm you want to remove the meal selection.
Once you click ok the Childs previous meal selection will be removed and the Childs background on the whiteboard will change to white.
You will now be able to click onto the child and make a new meal selection.