The wax or gel pens are really great, especially for children, because they are so buttery soft and beautiful painting. In addition, they can unscrew itself and thus does not break equal to the entire pen off when the child impresses too. A deduction there but because easily fall off from the pin crumbs. Once on the floor, they rub up pretty quickly and dyeing parquet or (even worse) a carpet stubbornly. So necessarily always use the table and afterwards look good where crumbs fell down. Nevertheless, all in all highly recommended.
