I sew on buttons, hem clothes and sometimes will repair small tears and repair seams. Otherwise, I toss torn socks, torn jeans (or I cut them into shorts) - I know wasteful. No, no, no to zippers (never learned how to do them). I will repair knit sweaters, if possible, especially loose knit ones.
When I was a Boy Scout leader, I taught all the boys how to sew their own merit badges onto their sashes. The Moms loved me - the boys not so much. From what I hear, the badges are now iron-on. Too bad. When my son went into the Marines (1997) he was one of the only guys who knew how to sew.