Exaggerated: David and his friends are only 3, but they still take helicopters to Mount Everest, jump out of exploding planes, and stop super secret evil organizations from taking control of the world, all without any adult supervision.
Downplayed: David and his friends are 12-13 and are seen out on adventures without adult supervision, yet their parents still know where they're going.
In this culture, kids are treated like adults and are expected to be able to take care of themselves at a younger age. Or alternatively; David and his friends' parents can trust their kids not to do something stupid so they let them have free range.
Alternatively: The acknowledgment of Infant Immortality in their world makes the idea of creating rules and restrictions to keep kids safe seem very bizarre.
David and his friends live in a town so small everyone knows each other, and thus they don't worry about strangers.
The story of David and friends takes place in an era where Free-Range Children were much more common and accepted due to a lack of certain dangerous technologies and/or knowledge of crimes against children such as pedophilia.
The parents are too protective of their children, treating them like toddlers.
Subverted: David and his friends do have parents who give them rules and restrictions to live by. They can't stay out over night, and they can't go very far from home without adult supervision. They are not allowed to do dangerous things without taking reasonable safety precautions nor are they allowed to fight crime.
Double Subverted: David can't stand the restrictions so he runs away on his adventures and now that he's gone his parents are okay with it.
Parodied: David casually tells his mom that he's going into a portal to hell for a few weeks. His mother is completely fine with it.
Throughout the series, David and his friends often go where ever they like and do whatever they want, but occassionally get grounded by their parents for coming back in late or tracking bloodstains on the carpet. Sometimes the parents simply won't allow Dave to go on another wacky adventure depending on whether or not it will suit the plot.
Alternatively; they are free range but are commonly shown to be hanging around a certain area (Oftentimes; this is when they are able to consult an adult in real life) and whenever they go outside the range are shown getting their parents angry or are in trouble.
The children have restrictions, but go on adventures anyway, either accepting the consequences of their disobedience or avoiding the consequences by lies and magic where no time passes while they're gone.
Parents are always around and giving the kids realistic restrictions so that they can't do anything that would be above their age level unless they have their parents' understanding and concern.
Enforced: "It's a kid's adventure show, so we need to have kids go on adventures. But we don't want their parents always hanging around telling them what they can or cannot do."
Officer: "Aren't you a bit young to be going on crazy adventures without adult supervision?" Kid: "Why yes, yes I am."
Invoked: David and his friends sneak off on their adventures without ever getting adult approval.
Exploited: David and his friends are kidnapped by a group of criminals who know they're not supervised.
Defied: David's parents simply will not allow David and his friends to go where ever they like and do dangerous things.
Discussed: "If you look at the statistics, kids have a better chance of becoming a professional athlete than being kidnapped walking home from school. They'll be fine."
Conversed: "Where are those kids' parents? These kids shouldn't be allowed to do these kind of things."
David and his friends have no rules or restrictions to live by and are thus able to do whatever they like. They decide to go biking through the tropical rainforest, but are quickly attacked by anacondas and other wild beasts. As Dave and his friends are being eaten one by one, David comes to the realization that none of this would've happened if some smart adult just told them "No."
David's parents practice Hands-Off Parenting, and as a result he winds up hurt or unaware of some dangers because they've never really given him or his friends a talk.
David is seen walking home from school by himself, and his overzealous neighbor calls CPS. David and his family are needlessly terrified.
David ends up smarter and more capable than his peers since he was allowed to learn how to live and be safe by himself.
Reconstructed: David and his friends have no rules or restrictions to live by, but only because they've all been trained in martial arts and survival skills by their incredibly cool parents. They can do whatever they want and are able to overcome any obstacles or dangers they come up against. All the adults know about the adventures Dave and his friends go through and allow it because they know they can handle it.
Do your parents know you're here? Better go back to Free-Range Children before you get yourselves hurt.