Erasable Markers
The claim assumes a non-porous face. On a melamine board that has aged, or on paper, the pigment sinks in and no eraser recovers it. Test an unseen corner before committing a classroom set. Ink left in place for days also bonds, so erase at the end of each session rather than at the start of the next. See whiteboard markers, whiteboard cleaner and erasable pens.
