NPD Group has revealed some of the results from a survey of US parents to find out how their 2-14 year-old children are spending money on entertainment. The key finding: 21 cents in every dollar those kids spend on entertainment is on digital content, up from 15 cents in 2009. What’s more, 50% of children have bought some form of digital media by the age of seven, although All Things Digital speculates that this is most likely using gift cards (e.g. iTunes) or getting their parents to buy it for them. And it seems music is to the fore in this digital trend. “One-third of kids report songs being the first type of digital content they purchased, followed by computer games and mobile games,” explains NPD.