I was once approached by a school that had purchased a lovely 3D printer, but didn't have anyone who knew how to use CAD (computer aided design) software to create the files to send to it. The machine came first. At that point, I'm happy to help teachers learn to use the software and the machine, but I wonder sometimes whether we've tried so hard to introduce kids to the "high tech" world of making, that we've undervalued the amazing things that can be done with some hand tools. Not too long ago, manual arts training (later called shop class, or industrial arts class) was standard in most schools, along with a stocked shop (typically wood or metal working). This is no longer the case, but many schools, in hopes of incorporating engineering into their curriculum, are looking at using tools like 3d printers and laser cutters to "get kids interested in engineering."
I'm not completely convinced yet that high-tech equipment is necessarily the right way to go, especially for younger kids. While 3d printers definitely elicit "oohs" and "ahs," and some neat objects to put on the family bookshelf, most kids can't go home and use the skills that they just learned. If the main goal is to make kids comfortable building and taking things apart,learning to work through failure, there is beauty in simple, cheap tools. The nice thing about basic tools (such as hammers, saws, glue guns, etc.) is that they have a low entry barrier. It doesn't take long to teach a six year old how to use a hammer safely, and it's pretty hard for a child to break it. Thus, it's fairly low risk to let them use one. Part of the joy of a basic woodshop class is that many of the kids can go home and have access to basic woodworking tools (or purchase them cheaply.) They've learned a skill that they can practice regularly, and on their own (with appropriate supervision as needed.) I suspect that I'm not the only engineer who can think back fondly to my first home "woodshop." I got it for Christmas when I was about 8. It was very cutting edge: hammer, nails, handsaw, more nails, some wood glue, and assorted wood odds and ends. I remember building cars and doll furniture. With the exception of the time that I left the glue gun on overnight and, in the words of my mother, "almost burnt the house down," I didn't do anything particularly dangerous. Most of the cars I built weren't exactly speed racers, and the doll table was uneven. Nonetheless, I was incredibly proud of them, and spent hours in the basement building (though I did have the hot glue gun taken away after the above-mentioned incident.)
"High tech" prototyping tools, on the other hand, are less likely to be open for kids to use anytime. They are often put on a special shelf in a locked room. There's the fear that they could be broken, so rules and regulations are put into place about who can use them, and when. They may be used as part of a class activity, or school sponsored program, but they're less likely to be something that a kid can just show up and use to try out an idea (particularly one that is likely to fail.) It's easy to understand why a school, which is probably having to make budget cuts, would be super cautious about who uses a piece of equipment that costs, typically, tens of thousands of dollars. Even "cheap" 3d printers aren't "cheap" when you look at them in terms of the typical public school budget.
So am I against 3d printers and laser cutters? No, not at all! If you can give kids access to them and let them iterate, and try things out (even things that might not work), go for it! But if you are on a tight budget, I'm convinced that buying a slew of hand tools and soldering irons (and lots of junk and scraps to play with) is likely to have more of an impact then a single 3d printer for which you must ration out build material. The ability of a hammer and nails to empower a kid to "build their own solutions" to problems is amazing.