This cute cupcake sashiko sampler is designed with larger printed stitch lines making it a good choice if you are looking for a project for a child who wants to start hand stitching. The manufacturer calls it a "finger training" sashiko sampler because it reinforces through practice making even length stitches.
Use sashiko thread and a sashiko needle.
You don't need a hoop to do sashiko stitching, you simply gather the fabric comfortably in your hand and stitch. This allows putting multiple stitches on your needle. However if a younger child has trouble keeping their stitches from becoming too tight, I know some have had a happier experience using an embroidery hoop to keep the fabric taught while stitching. The important thing is they enjoy the project.
Finished stitched area 12" x 12".
The printed dash lines wash away easily after the stitching is finished. This fabric and the sashiko thread will become prettier after being washed a few times. Be sure to finish any raw edges first, but then you can throw it in the washer and dryer.