Availablity is huge, but if the product is not engaging then it doesn't matter if they are everywhere.

I was taking my kid weekly to my local shop and was buying age appropriate books for her . She loves the superhero characters (she knows way more about them than she should), watches the cartoons and is interested in seeing the movies, but the books were not entertaining enough to her for me to keep plunking down the bucks for them.

The stories didn't have enough going on (the 5 minute read) or they were too continuity heavy without having good in issue explanations as to what was going on. A kid shouldn't have to go back to three months worth of previous issues to get what is going on the current issue.

Also, a lot of the material supposedly written for a younger audience, is really dumbed down. Kids know when they are being written down to. They want the real character. When I was growing up, I would never read the Spider-Man (Spidey) stories that were written for kids. My kid is the same way. I bought the main-line stories, but finding books that were appropriate was difficult.

To echo Matt, the kids haven't really changed, but the product is not made to suit them.

Added to the availability factor is that kids today are being raised by a generation that also had limited availability issues due to the direct market. How can a parent effectively pass down or encourage a hobby or passtime they themselves may have had no history, as well as have it compete with other interactive interests like sports, games, etc.? Unless that parent is predisposed to encouraging the sequential reading aspect of comics, or appreciating the art that goes into them, comics have an uphill climb against those other interests.

When the parents are as unfamiliar of the product as the kids are, it escalates the problem of reintroducing a generation of children to a product that hasn't been readily available for as much as 3 decades.

Bryan Eacret, I agree with you about books that only take five minutes to read, but multi-issue stories have been around for a while.  But what it was is that they ahd the main story and so many subplots that they could be read separately.  (Think of JB's Negative Zone story...)

When I was reading, there was the X-Men story about the Brood, Dark Phoenix, The New Teen Titans Blackfire Saga, the Terra story, the Raven story... but they were so well-written and engaging and most importantly, weren't being written for the trades.

Some comic shop shelf distribution can leave a lot to be desired.  Next to the Marvel books are books with scantily clad women (far too often, some fetishization of Wonderland), boobs, maybe a Garth Ennis book like The Boys "Herogasm" that pretty much shows a guy getting a bj or even worse, Ennis' "Crossed" that is basically carnage and bloodshed on every cover.  Censor them?  No, but man, if I were a parent and brought my kid to a comics shop, I'd be a little wary.  Would a kid feel much of a connection to this stuff?

What is keeping kids out of comics?

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Multimedia, videogames, dvd movies, Netflix etc.  There are more alternatives of entertainment for kids today. 

   Most of the questions have been answered by Jason and elaborated upon.  I personally recall a day when I could get by on my first day jobs out of high school (roughly a click above minimum wage in the late 1980s) while collecting at least a half-dozen comics per month.  At the time, they were pushing $1.00 and didn't start to go beyond that until after the big speculator crash in 1993.

   By then, the damage was done.  Newsstands rarely carried the books.  The stories had started becoming unreadable because the pacing kept getting thrown off by crossovers and the departure of creative and editorial teams which seemed to know what they were doing.  And finally, my tastes in storytelling and entertainment just switched away from monthly comicbook titles from the Big Two and whatever indie publisher wasn't handling Japanese comics (I was never into the "bad grrls", vampires and zombies).

   Today, I can't think of anything that I'd want to give my nephew and nieces off the shelves.  Their sources of entertainment and leisure time are completely unrelated to mine.