I couldn’t be more thrilled that my older son is mechanically inclined. His favorite thing to do is sit around and read what we call his “tool book” — a grown-up reference material that I bought from the Barnes and Noble clearance section, which features more than 200 pages of tool pictures and descriptions. At four years old, we’re already pretty sure he’s going to be an engineer or an auto mechanic or something else where he works with his hands.