Bribing toddlers can be counter-productive, according to Vanessa. Instead, the 28-year-old coaches her young charges how to play together – for $450 an hour. After all, play dates are no trivial matter. They can decide a child’s future.

Vanessa, who declines to give her last name, is one of a new breed of play date experts that help children prepare for admission to New York’s elite kindergartens. As part of the admission process to these schools that charge up to $40,000 a year, four-year-olds must attend a playgroup where they are tested by teachers for academic ability and their social and emotional IQ.

Play date experts set up situations to see how children respond and then make suggestions for improvement. For example, if everyone has to write down his or her name but there are not enough pencils, they must wait their turn.