I don't know...I think sometimes there are misunderstandings about children that people have with this passage.
I think what kids have to their benefit is that they're not too full of themselves, they are loving and hopeful, and while they're trusting in a way adults aren't, the brightest ones are inquisitive. That last aspect is what I think a lot of people forget or severely underestimate in children. Kids really aren't stupid, and they're like sponges for knowledge. I know that when I really got interested in something as a child, I kept digging until I got answers that made sense.
When I was 5 years old or so, my parents had given me books both about science and faith, and had presented both authoritatively (as in, treated them both very seriously). At about that age, I realized that I would have to find some way to reconcile the two. I understood very well that literalism meant I'd have to rule one of them out as a lie. So I pulled out my children's Bible to look over the Genesis account, and started to notice something very interesting: that the description of how the cosmos formed looked an awful lot like the Big Bang! An explosion of light, a separation of matter and energy into separate masses (light separated from dark), cooling into planets, stars, and heavenly bodies...that moment of realization was an INCREDIBLE one. And I was five, MAYBE six years old.
Healthy kids ask questions, and they're also able to tell when adults are BS'ing them. So I don't think we're being asked not to question...even if we're to use children as our example. Unfortunately you DO get a lot of dangerous misinterpretations.
Here's an interesting passage to look at, about the ideal human mindset. In this case, Jesus has sent some of his disciples into a town that treated them very badly. They were very disturbed about what happened, and (as usual) St. Peter shot his mouth off. At that point Jesus explained the mindset they ought to have when they went into towns in the future. This comes from the gospel of Matthew:
"I tell you the truth, it will be more bearable for Sodom and Gomorrah on the day of judgment than for that town. I am sending you out like sheep among wolves.
Therefore be as shrewd as snakes and as innocent as doves.
"Be on your guard against men; they will hand you over to the local councils and flog you in their synagogues."
Nowhere did Jesus tell them not to use their God-given intellects, and not to question the situation they were in--He just asked them to combine their knowledge and intellect with a conscience.