Facial recognition is no longer just being used to unlock iPhones, tag Facebook friends and scan crowds for security threats. It’s moving into summer camps, youth sports tournaments and schools.

Parents at summer camps across the country can opt into facial-recognition services to receive photos of their camper without having to sift through hundreds of group shots for proof that little Susie is having a good time climbing ropes. One facial-recognition software manufacturer has proposals in front of several K-12 public school...