Kids and idioms

     When I was a kid it seemed like my grandparents and my parents spoke only in idioms.  All you had to have to be a parent was a head full of these phrases.  There was a saying for every situation.  Don't beat around the bush.  Curiosity killed the cat.  Knock on wood.  It's time to hit the hay.  Now that I think about it, I don't think I was ever told to go to bed.  It was always "hit the hay."
     Though I learned dozens of my idioms during my formative years, there were still a few that I didn't encounter until later.  These were the ones that had more adult themes.  "In like Flynn" was something I probably picked up in high school.  I was probably in secondary school by the time I found myself "between a rock and a hard place."  "High as a kite" and "Devil's advocate" are also late comers to my lexicon.  I never heard of "full monty" or "wag the dog" until the movies were released.
     Non-English speakers are taught idioms in their English classes.  Autistic children spend time in school learning  how to decipher idioms because they, by nature, are a literal bunch.  I was surprised to discover that normal, American born children have idioms in their lesson plans these days.  Starting in grades 4 - 6 and continuing through high school, idioms are part of English class.  Have parents lost the phrase book?  Why aren't kids absorbing colloquialisms from the world around them, like learning cuss words?  I'll bet cuss words will never have to be taught at school.
     I can't seem to find any scholarly material on why kids don't know idioms, so I have come up with some of my own ideas.  First, I think there is more give and take between parents and children these days.  Instead of issuing orders like, "Get that chip off your shoulder," today's parents are more likely to ask, "Why are you still angry about what happened last summer?" Parent's don't want to lay on the guilt like in the old days, so today's youngsters are less likely to hear, "I bend over backwards for you."
     Another reason certain expressions might not be used is that we have moved so far away from our agricultural roots.  What's the sense of telling a child, "He ran around like a chicken with his head cut off," when the last time someone in the family slaughtered a chicken for dinner was three or four generations back?  The same goes for "having an ax to grind."  If we need to chop down a tree today, we fire up a chain saw.  Horses have gone from necessities to luxuries, so what does, "Hold your horses," mean?
     I might be going out on a limb with this one, but I think church attendance has fallen off.  When children don't receive religious instruction, they don't "get" certain references in speech.  They never learned about the good Samaritan.  They don't know that Thomas doubted.  They don't know about Jobs' troubles.  Not being Bible readers, they wouldn't understand that knowing something "chapter and verse" means knowing it completely.
     I think idioms are more than pat phrases.  Besides being references to whole stories, they can be images.  Doesn't it make you smile to think about some mangy cur barking up at limbs and leaves when all the squirrels are two trees over?  Imagine a ten foot high pile of Hurricane Sandy garbage, but no kitchen sink.  Idioms make our speech and our thoughts richer.  An idiom user might be inclined to be a creator of some new idioms.  Here's one I just thought up - dizzy as a carousel horse.  A person with an insurmountable job might use an idiom to get to a quick solution of the problem:  How do you find a needle in a haystack?  Just take your shoes off and go kicking through the hay.  You'll find it.  And on that thought, I'll take a hike.