I am now teaching my 9yo DGD to quilt and we decided that mistakes give the project their very own character. Trying to make it perfect was taking all the fun out of it for her. She is currently making placemats and now that she has stopped worrying about it being perfect she is actually doing much better. I did have to point out some mistakes that I had made in some of the quilts that I made. The last quilt that I made she noticed the "big" mistake that I made but told me that she would keep it a secret from DD for whom the quilt was made.