I'm 31 (32 in October) and grew up in southern California. Like most Americans my age, we learned to "print" in Kindergarten. (Well, I and many of my fellow students could already write our letters before we started school, but we were taught the "correct" way and had to practice it in Kindergarten and first grade.)
For you non-Americans who are still confused by the terminology, we use the word "print" to mean "write letters which look like Helvetica, but usually quite a bit messier." (Except for the lowercase "a" ... I guess a font like Futura would be a bit closer to what we were taught.) So if you see "please print" on a form, that doesn't mean you should stick it in your printer. Just write using your best impression of a sans serif font. :-) They just want each letter written separately so the OCR software can tell where each letter begins and ends. Usually it's best to use all uppercase on forms, just in case their OCR software is dumb. (The US Postal Service has magic OCR which can read anything, whether typed, printed, or written in cursive. But other government agencies don't get to use the USPS's OCR, and typically have complete crap instead.)
In second grade we were taught to type. (Did anyone here else learn to type with the Wonderful World of PAWS on an Apple //e? That was the one where you had to type in order to get the cat across the screen so it could reach the ball of yarn, or whatever.) I don't think learning to type before learning cursive had any effect, but maybe it did. I don't know.
Finally, in third or fourth grade (I can't remember which) they taught us cursive (what the teachers called it) or handwriting (what most students called it). Ours was an old-fashioned loopy kind. I can't find any examples of it online, but it was written on a long green strip of plastic, mounted above the chalkboard in all of our classrooms. Some of the capital letters are different from any of the modern samples I can find in Google image search. All the modern samples I've seen have a separate crossbar on the capital "F", for example, whereas ours had the swoosh in the bottom left continue across the stem, like the ones in the Declaration of Independence. No wonder so many people get confused by my "F"s.. I hadn't realized that most people don't write them that way anymore. Note that not all of our letters looked like they were from the Declaration. We didn't have those funny tall "s"es, for example. :-)
After they taught us cursive, we were supposed to start using it (pretty much overnight) and write everything in cursive using ballpoint pen. (In the lower grades we had to print everything in pencil.) That abrupt transition is probably why people hate it. Imagine learning to type on qwerty for 3 years and then having to switch to dvorak overnight. (Or the opposite.. the direction doesn't matter, it's the abrupt switch which people hate.) We'd all have better handwriting if they'd teach us one system and stick with it.
Most of us sucked at it. Some of the girls practiced it nonstop and ended up with pretty nice handwriting (except for those stupid hearts on their "i"s and "j"s, of course). The other girls and nearly all of the boys never developed very good handwriting. The 4th-6th grade teachers all insisted that we'd never be allowed to print again and that it was vital that we improve our cursive. But of course at the junior high (7th & 8th grades) only about half of the teachers cared. And in high school almost no teacher required cursive (aside from English teachers on the verge of retiring), so at least half of us reverted to printing for tests and such. By my junior year of high school we were expected to type all of our papers anyway.
In college I reverted to printing. College caused my printing to mutate quickly, as speed gained importance, as well as the ability to write while not looking down at the paper. As a result, it is illegible to most people, except a few who have learned my quirks. It is now rather difficult for me to print legibly, unless I write in all caps. (My high-speed printing has almost no caps, so forcing myself to write in all caps, eg. on forms, slows me down enough to make it somewhat legible.) As a result, my cursive is now more legible than my printing, which was certainly never the case before college. In fact, I never would have expected this before I tested my writing on a piece of scratch paper a few minutes ago. All that cursive practice back in elementary school must have stuck in my muscle memory, where it remained pretty much untouched, even while I was destroying my ability to print.
Now it's rare that I write anything. (No surprise there. Who does write anymore?) My girlfriend insists that my writing is illegible and always fills out forms and applications and such for me, but I think that's based only on my printing. I think my cursive isn't too bad. At least not compared to most Americans under 40. But no one ever gets to see it.. I pretty much only use it when writing checks. And as a 31-year-old, how often do you think I do that? :-)