There are few traits more common among good scientists than curiosity. Almost by definition, people working in the field of finding out new things must have the desire to seek out new things. And yet, everyone treats it like a congenital gift. You are either a curious person, or you are not. I've rarely heard anyone say they would like to become more (or less) curious.

Even still, I googled the question "How do I become more curious?" and all the answers could be summed up as :

Ask questions
Ask more questions
Keep asking questions
Be humble and persevere
Ask a few more questions.

And indeed, the act of questioning is central to curiosity. Humility is also important because one does not ask questions if one thinks they know all the answers. But today I want to probe what the circumstances are that lead people to be curious. An easier group to investigate would be children up to school age, because they all go through basically the same routine till age 15. We know that young children are naturally curious; their every behaviour is exploratory, their every action an implicit experiment, the little tykes are learning machines. But as those same individuals leave their secondary schooling, you start to see that natural instinct wear away in a large percentage of them. In the quest to increase the working scientific community and improve science literacy in the general population, this is a systemic catastrophe. How does our education seem to dull the very blade it seeks to create, and how do some sharp ones still emerge?

There are a few more qualifying factors that might help us tease open this mystery. But first, a little background.
One of the ways I channel my drive for science communication is by being a part of the outreach team at the Tata Institute of Fundamental Research (TIFR), an advanced research facility in my city. A few times a year, they invite the public into their campus and labs to showcase the kind of work that researchers do, how and why they do it. A large portion of the audience is usually school and college age students, and I frequently assist in escorting the boisterous groups through their visit. Over the years, I have had to opportunity to observe a not insignificant sample of kids in this environment, and some of the observations I have made from this have prompted this line of questioning.
There have always been distinguishable groups of people, some who did have this elusive trait of curiosity and seemed to probe their surroundings with the prongs of their questions, and other who for whatever reason didn't seem to exhibit the trait. (Notice that I'm consciously not saying that they were not curious; because they may be in a different environment, just not this one). So what causes this preferential exhibition? Let's take a few pot shot guesses and try to dismantle them (like any good scientist would) and see what we can scrape together from all the remains.

Let's get the easy ones out of the way first.
Maybe they did have questions, but either lacked the communication skills or the confidence to display it in the situation. This is not an unreasonable thought because I know from first hand experience that TIFR can an intellectually intimidating place to be, surrounded by people who objectively know more than you. But categorically, if you never express your curiosity and attempt to find answers to your questions, is there any utility to the curiosity in the first place?

Another hurdle may have been prior education. If you don't know how to box and step in the ring to spar with a competitor, you're going to have a bad time. Considering the sorry state of education in a lot of schools here in India, it's not a stretch of the imagination to assume that they were not well informed about any of the basic fundamentals, or more critically, never told that they could know more than what was in their book/exam or ask for it. A significant number of children seemed to come from this schools that institutionalised this idea within them, and couldn't seem to fathom that they should be questioning the person speaking.
Here is where some interesting separation started to occur along other well defined boundaries. It was statistically apparent that the groups of children that came from "better" (read: from a higher socio-economic stratum) schools seemed to be more open to the idea of questioning what they saw/heard. (This was by no means a universal phenomenon, and we will discuss the [large] exceptions later) This might sound obvious since I used the word 'better', but let's unpack it.
These schools were not government aided public schools, but more privately run newer institutions. They followed different syllabi, probably attracted better teachers, and as a result created a different learning experience. But before we give all the credit to these uber-schools, there is an important dependency to note. The children with access to these schools came from a completely different socio-economic class that those that attended the public schools. To evaluate the causal factors of the development of curiosity, we must try to isolate the effect of the tuition and the socio-economic background (because one can be much more easily replicated than the other).

It seems valuable to try to unpack what characteristics of the better socio-economic upbringing allow this trait to foster, because maybe it can be replicated for people outside this group as well.
One would seem to be the likelihood of the parents being well educated as well. The existence of a couple of experienced mentors to guide one through the process would intuitively improve the learning experience, by proving support and direction.
Children who are first generation learners in their family are less likely to receive this support. But if we know what is lacking, we can try to provide it. Intelligent mentoring could fill the role and provide a role model for the children to aspire to outside of their teachers.
People from the former group also categorically have access to more resources, allowing them to tap better sources of information and direction (like continuous access to the internet, libraries and subject experts). This can be replicated in part for the latter group, but as some of the exceptions will show, it may not be all that necessary.
Another factor could very well be that the safety net provided by a providing family can supply the security required to aspire to pursue less secure ventures for their future careers instead of having to aim for a less ambitious but more stable job that guarantees them standard employment and income. And the pressure to get a job sooner rather than later would rule out exploratory higher education as well.
From a few more empirical observations, it has come to my notice that the school also has a large role to play. By acting as magnets for both brighter students and teachers, they are able to have a far higher than average standard of education, and because they are less pressured to pass standard competitive exams, can focus on the true learning process instead of rote memorization.

But now, let's visit the exceptions, and see which traits are necessary, but not sufficient.
It is another frequent observation that students who come from such schools are not remotely interested in the learning process at all, possibly because the safety net provided to them shelters them from the need to perform or work hard. For these people, all the resources and guidance available to them is practically wasted. So clearly just resource availability is not enough, the internal motivation to do it must also exist.
Is the desire and drive to do learn both necessary and sufficient? Not entirely, but maybe. As we enter a more information dense age where access to knowledge is more egalitarian, people with fewer resources can access learning tools previously reserved for the ultra-elite (an excellent example of which is the free availability of lectures from world class institutions of topics of every subject now, sharing the knowledge of the world's best teachers with the world).

So then the question becomes, where does this internal motivation come from, and how can it be created and nourished?
Obviously the question that all of education is trying to answer, but I'll take a stab at it from my view and experience.
A number of people in my life have asserted that I am an internally driven person in a few areas (like science/parkour). To me, I don't usually think of an abstract force inside me that inextinguishably drives me to do more of these things. I only hazily remember how it developed from being something I found cool, to getting better at it over time and through work, till I reached a point where I no longer needed any external support and sustained itself. Almost as if motivation was a fire that needed to be lit by a spark, nurtured in it's early stage, provided with adequate kindling early on and protection from stray breezes (because that's when it's most likely to be easily extinguished). Once the fire is well and truly going, it is mostly self sustaining. It still needs more fuel every now and then, but by then its large and warm enough for itself and to light a few other fires as well.

So if you feel that fire within you about something, light a few more.