One of the bullet points in the job description is programming. I figure out activities and crafts, stories and games, literacy tools and educational aspects that can all be blended so that it's not just a half hour or hour of uncontrolled insanity. Sometimes programs dissolve into that but we usually do start with a plan and, when possible, there's still method to the madness.
One of the important part of planning is knowing what age group I'm working with and being able to plan accordingly. Such it is that when programs are advertised with an age group, that's the age group I want, that's the age group I expect, that's the developmental level I'm looking to walk in the door. Children grow and change incredibly fast, as anyone around them can tell you. When I worked strictly with infants and toddlers, three year olds were huge kids to me. They could talk in complete sentences and were mostly potty-trained!! Now working babies through teens, I'm stunned at times how young some of the teens seem (really, you're 14?) or how old some of the eight year olds are. I do still think that a child who is actively walking doesn't count as a baby anymore, but that's my choice of brackets.
And there are mixed ages and groupings that work, but there are times we expect something best suited for an older child. This is something I've run into with teaching children to knit. Most children have the manual dexterity and understanding to learn how to knit about the same time they learn to read and write. For some children, this is age four, for others it's closer to six. When you're working one on one with a child, you can choose based on the skill of the child. When I have a group, I really prefer eight and up, though I'll stretch it to seven. This gives me the opportunity to have children who have all achieved that manual dexterity and who will be able to read a knitting pattern, even if they need help translating some of the meaning or symbols.
Often, it's adults convinced of their child's high level of maturity who throw a spines-out hedgehog into the mix with programming age parameters. Their child is old enough, mature enough, with enough manual dexterity, whatever it is they think they need to say to get around the age barrier so that their child is granted whatever treat or program the parent has promised. [I've also seen this in reverse where parents thought their ten year old should be allowed to thunder over equipment built to support a two year old--it works both ways.]
Sometimes this is not unlike watching parents attempt to convince carnival ride attendants that their 3'8" child is really 4' so they can go on a ride not safe for shorter children.
Granted, I don't expect to cause whiplash in the programs, but perhaps I'm suggesting books to the kids or reading a select chapter. Most six year olds are not going to be ready for the battle scenes in Brian Jacques' books and or the opening pages to this year's Newbery winner--Neil Gaiman's Graveyard Book. Similarly, most ten year olds are really moving beyond books about a precocious kindergartner who has little grammar and less discipline.
When I set an age parameter on a program I'm trying to create a productive atmosphere for learning, communicating, and interacting. When the rules "just have to be bent" because a younger child wants to participate, we're teaching the child that those rules don't apply to them, that they don't have to wait, or grow into something or be aware that they are too old for other things. Quite often older children don't get anything special and are required to share it all with younger children, which isn't fair to anyone: not the older kids for whom the program was meant, the younger kids who aren't ready for the older books, or the programmer who is now having to focus unfairly on the younger kids needing extra help or completely rework the program on the fly. Librarians are good at programming off the cuff and at a moment's notice--but the point is that we've planned in advance here.
And truly, how many ten and eleven year olds do you know who want to hang out with six year olds all the time?
Knowing something will be a special treat when they're older, or taller, is not a horrible thing. Following the rules about something like age now just might set a precedent for down the road when it's driving, curfew, or dating. But in the meantime, please don't make me or any other program planner the bad guy. I can't control your child's age or height--but then, I'm not the one who promised them they could ride the ultra-looping-roller-coaster or go to the program that's for the big kids [or preschoolers] only.