[Slaughtahouse]

As long as they have supervision, grade 4 (10 years old?) is a perfect time to introduce them in my view.

There is no guideline. It's just common sense. Any equipment that could present some level of risk to kids should be supervised. Maybe list the risks out to the other parents identify the impacts. I mean... what is the concern? Kids eating the plastic filaments? If your 10 year old is eating that... you have bigger issues.

You can learn a lot of about design, constructability, how materials behave, prototyping by messing around with a 3D printer. That's what STEM / STEAM is all about, right?

Even video games these days are implementing STEM like Nintendo Labo or Minecraft. I went to the Ontario Science Center a couple years ago and they had labs for kids with all kinds of stuff.

When I was already 15/16 years old, I was in shop class using a band saw, drill press, sheet metal bender, CNC machine etc. That's only a few more years and the risks are WAY higher lol.

 

[IEATFISH]

My daughter had printers in her class around that age. They did small projects like making name plates for their desks (simple rectangles with their name extruded) that they then painted. Little crafts and small projects are awesome for introducing them and starting the ability to visualize 3D in software early.

 

[Derc7186]

When my kids were 7 years old, they used this flashforge to create their own models in 123d sculpt. They know it's daddy's machine, so they've always been supervised since they know it's daddy's. I just do the hard stuff, bed levelling etc for them.