Pottery Wheel is great for every little budding artist. I let my little "artists" lose with the wheel and my 7 year old was able to make a decent small bowl - he's pleased with the result. My daughter LOVED to "spin" the clay!
One aspect that I especially love about the Pottery Wheel is that this is a sensory integration activity my son. SIP children just think they are having fun when they are actually working strenuously at building essential skills with their bodies and better neurological systems while playing with the Pottery Wheel.
ps: don't ever leave your 7-year old son alone with clay encrusted hands . . . not even to go to the bathroom . . . he will follow you and proceed to flap and slap his hands together all the way from the kitchen table to the bathroom . . . . and in the process, completely splatter every surface of your house in his path with a smattering of little white clay spots.