American businessman and philanthropist Andrew Carnegie's public library legacy was built on a boyhood dream: to acquire knowledge. Carnegie believed in "the meritocratic nature of America," that anyone "with the right inclination and desire could educate himself" and therefore succeed, and that libraries should contribute directly to that.

So what are libraries doing lending out toys and holding game nights? Aren't American kids' test scores lagging behind those of pretty much the rest of the world? Shouldn't American public libraries be, as Carnegie wanted, educating? Recent studies, and librarians themselves, say otherwise.

In a study with 70 six-year olds, psychologists at the University of Colorado found that the children who engaged in more free play had a "more highly developed self-directed executive function" than those who had spent more time in "structured activities," that were adult-led rather than child-initiated.

Self-directed executive function is "the ability to generate personal goals and determine how to achieve them on a practical level." In other words, a child with a higher level of self-directed executive function may be better equipped to complete a homework assignment on her own while one with a lower level may need more guidance and direction.

So why does more free play seem to lead to better executive function? One possibility is the flexibility hypothesis, says the New York Times. The hypothesis says that an animal's playing "leads to mental suppleness and a broader behavioral vocabulary," which "helps the animal achieve success in the ways that matter: group dominance, mate selection, avoiding capture and finding food." In other words, an animal that play-fights, one moment being dominating and being submissive the next, may more easily adapt to sudden changes later in life.

A recent piece in the Boston Globe supports that theory, saying that people "who exhibit high levels of playfulness—those who are predisposed to being spontaneous, outgoing, creative, fun-loving, and lighthearted—appear to be better at coping with stress."

While in theory more unsupervised playtime for kids is a great idea, it is not a luxury available to everyone. Some toys may not be affordable to low-income families. Adaptive toys, those for special needs children, are often two to three times the cost of the original toy, says American Libraries Magazine. Some children may not have a safe place for unsupervised play, and in 2013, almost half of households with children and married partners had two working parents, while child-care costs all over the country are going through the roof. This is where toy libraries and libraries in general come in.

The first toy library was established in Los Angeles during the Depression. A dime store manager noticed that kids were shoplifting "making toys from the items, such as using thread spools for wheels of cars." The manager informed Gertrude Peddie, the principal of a nearby school. Peddie then "went to local civic groups and together they formed Toy Loan, collected donated toys and operated out of a garage."

Toy libraries nowadays do much more than loan out toys. The USA Toy Library Association's mission is to "offer an important dimension to America's educational program by providing another environment of abundant play opportunity supplemented by a collection of high-grade toys"; to "provide disabled children with quality, specially-adapted toys"; and to "help parents to play with and provide play experiences for their children while becoming more informed consumers of toys."

library in Decorah, Iowa offers an affordable subscription: $45 for families to use many toys as they want for three weeks, and $35 for grandparents "who don't want clutter around their house all the time."

While toy libraries target younger children, libraries that offer video games draw teens. A librarian at the Houston Public Library tells NPR that offering game consoles and iPads "results in a 15% to 20% increase in the circulation of books." The games themselves also seem to help struggling readers, with some reading text in video game format "that was up to eight grades above their reading level," says Constance Steinkuehler, an associate professor at the University of Wisconsin.

Having gaming available at libraries has other advantages as well. It gives lower-income youth the chance to play games they may not be able to afford; offers teenagers a safe place; and helps teens understand that the library is a place where they can belong.

But what about the supposed link between violence and video games? One study showed that the more kids play violent video games, the more aggressive and violent they were. However, the study failed to account for other factors "such as violence in the home, abuse, and mental illness," or the fact that "the rise in popularity of video gaming has not been matched by a similar rise in violent crime among adolescents who are most likely to play them."

Another study suggests that it's not violence in video games that causes aggressive thoughts and behavior but it's losing at a game, violent or not, over and over.

Either way, most libraries have avoided the controversy by offering only E for Everyone or PG-rated games, says Dames and Dice, or keeping M-rated games in a separate room for teens who are over 18 or have permission from their guardians.

The availability of toys and games helps to establish libraries as a third place, as Kotaku says, a place between work or school and home, for education and for play, which, some would argue, are one and the same.

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