There are some really awesome male quilters out there, and men who design fabric as well. It's just another outlet for creativity. A lot of Montessori themed schools use sewing to teach hand eye coordination for kids. These are all skills that will help them later in life, being able to make functional items and repair them. :-)
My son who is 8 started sewing by hand about a year ago, then we moved him up to the sewing machine recently. What I did with my 6 year old daughter was she worked the foot pedal and I helped her steer the fabric so she wouldn't get hurt by the needle. You could have him hand sew some of the stuff, or just sit next to him and have him go really slow with the foot pedal. For his first quilt, he learned how to tie a quilt. The kids love to pick out their own fabric and design a simple quilt pattern. My son is entering his first quilt in the fair this year, he is really excited. Next he wants to learn carpentry from his dad. LOL
My fondest memories of my grandmother involve learning to sew, I think teaching them would be awesome for both of you.