As another reviewer already indicated, these are *supposed* to be dry erase markers, but they fail miserably in that regard. A fresh marker (< 15 minutes of writing) writes well and erases reasonably well, but after that you have to scrub with all your might, and you're still left with pigment goo on the board. I literally spend more time erasing than I do writing.(I think Bic has found a way to dispose of its hazardous waste: fill pens with it, and then sell them to consumers for a few bucks each!)Get with it, Bic. These pens are terrible. Did you folks fire your entire product testing department?If you or your employers are dead set against using a chalk board, get the Expo markers instead. The non-black colors may be too light for some (good when fresh, quite light when dry), but at least they erase like they're supposed to.