Growing preschool-tutoring market worries some development experts

3 year old Sanjana Rao learns numbers with tutor Lilian Yu at the Columbia West Kumon Center in Columbia, Maryland.

Preschoolers and kindergartners are among the fastest-growing markets for after-school tutors as anxious parents hope the early assistance will help their children get into the best colleges. Some child-development experts worry the trend is age-inappropriate, but a recent study may bolster the movement: Entering kindergarten with elementary math and reading skills was the best predictor of later academic success among nearly 36,000 U.S., Canadian and British preschoolers, according to the researchers' findings. TIME