Wiping advice...

My just turned 3 year old is potty trained, but she doesn't how to wipe very well so I usually just wipe for her. I take her to the gym where they have child care and they took her to the potty one day. When I went to pick her up, they said they took her potty but she didn't know how to wipe. They said it in a way where her not knowing how to wipe was uncommon for her age. So when did everyone's kids start wiping themselves and do you have any advice on a good way to teach a 3 year old?