I bought a set of these for high school students. They're great because they're small enough to keep in a pencil case, won't splinter like wood, and are economical. I like that they are crisp because kids can see the grid and adjust it before drawing the line if needed. Also, there's no hole, meaning kids can't stick them on the end of a pencil and twist them around. A student broke his, but it was intentional and not easy. I will for sure buy this again.