For those with kids who love tablets, you can buy a crayon stylus:
http://www.amazon.com/Homade-Universal-Crayon-Capacitive-Stylus/dp/B0099IQHF6/ref=sr_1_1?ie=UTF8&qid=1379468437&sr=8-1&keywords=ipad+crayon That way you can use a beloved activity as incentive to practice holding a pencil.