Instead of fixing it myself, I had my first-graders help take off this old latch and doorknob. We looked at the guts, called out the phillips head and flat screws, then went to the hardware store. A few days later, we put the new one on. The kids took turns driving the screws. Many adults have little sense of exactly how a doorknob works, though we've used them for years. Now these kids (boys and girls) have a basic working knowledge of what happens every time they turn the knob. Cool stuff.