A 10-year-old San Andreas boy tipped police after he saw two young girls in a sandbox dipping their hands into a plastic bag and powdering their faces with a strange white substance, later determined to be methamphetamines. The girls, ages 3 and 4, apparently were not harmed. Janete L. Davine, 33, the mother of the younger child, was arrested for investigation of possessing more than 2 1/2 ounces of methamphetamines, the potent stimulant also known as speed. “I have worked drug undercover duty for seven months, but this is one of the most bizarre cases I’ve ever come across,” said Calaveras County Sheriff’s Deputy Joel DeGraef. Deputies said the boy asked one of the girls what was in the bags, and the youngest child replied, “That’s my mommy’s powder.” The 4-year-old girl was later returned to her mother, but the 3-year-old was placed in protective custody, officers said.