Below are some of the products that we use here in studio - many of them will be helpful to your child at home as well. I buy most of my supplies from Amazon so I thought I'd share my list with you here. If you click on the photo it will take you to the place where you can purchase them. This page contains affiliate links.
Always use new thread because old thread can make the sewing machine dirty. Thread that is 5 years or older would be considered old.
Pins - we use quilting pins because they are large and easier for little hands to manipulate.
Pin cushion: Large tomato is for storing pins and needles small pepper is for sharpening.
The hand stitching needles we use are either size 18 or 22 Size 18 is shown here.
The 4411 Singer is what we use here in the studio. It is a workhorse. Also consider that kids need someone else in the house that is familiar with how to thread and clean the machine.
Good Book for Beginners:
And volume two:
The loran threader that makes it easy to thread large needles for hand stitching:
The seam ripper is our friend :)
Cleaning brush for sewing machines. Read your manual regarding cleaning your machine after each project.