How young is too young to start stitchin'...?? Perhaps when they can control the urge to stick everything in the mouth, is a good barometer as to when to start! My little ones started out with the thick plastic needles and some burlap with yarn for the thread. You can also use those flat plastic mats with the little squares that come in various shapes and forms. I also found some little sewing kits with the pre-punched holes in felt for making butterflies, purses, pillows, etc. that include all the beads and baubles to go along. Did we actually ever finish any one of those projects? Um, no. But they did get much practice making huge tangled weird messes with a needle and yarn...and believe me, that was just as satisfying!
However, by the time children reach age 5 or 6, they seem to become much more interested in the 'real deal'... forget the chunky, dull plastic thing...give me a real needle that's really sharp and shiny and some real thread, please Mommy. And also give me something that's really 'work' to do, too. My children are just not as convinced that the contrived, brightly colored crafty things aimed at kids are all they're cracked up to be...or as incredibly cute as their mother thinks they are. In their sheer desperation and determination to get to use a real needle and thread in the first place, they may sort of go along with the cutesy-crafty thing, but most of it, I have to admit, is either too silly or too complicated and just is not 'real work' like grown-ups do. At least that's the expounding sentiment I've gotten in my household!
So let's just give 'em some real mending to do! Somewhere around late 4, 5 or 6, they can begin to handle this kind of thing (age 4 you might want to transition with the metal yarn needles that are larger and not so sharp). Just make sure that you keep an eye on where they put their needles down...absent-mindedness is still an issue here...which I suppose never really changes with time, I'm afraid. Mending certainly falls into the 'real work' category and, once they get the hang of it, this saves mom eons of time in doing all the mending and button sewing that remains a constant in any household with ready-made clothing these days.
We have plenty of leggings, socks, tights, undies, and missing buttons to keep any industrious child with a desperate urge to use a needle and thread in worthwhile bliss for hours! Small mending projects are great for many reasons: 1.) most are short and simple for lagging attention spans, 2.) it's pretty difficult to mess anything up too much, 3.) it's useful 'work' that grown-ups even have to do 4.) there's a fulfilling sense of accomplishment in a job well-done...without a huge amount of time and effort, and 5.) this is a biggie, they actually get to wear things they haven't worn in months because mommy never gets around to mending it!
So all in all, I say mending and button sewing is a win-win situation all the way around! And for some more creative ideas for kiddos with needle and thread check out this and this, this and this,...oh and this. I see your contented smiles already!