A little real-world exercise for your kids: do you have one of those cans of bolts, nuts, screws and washers sitting around the house that you just keep intending to sort out so you won’t have to dig through it when you are looking for a bolt to replace the one that just fell out of the lawnmower but you never get them sorted because you spend all of your time grading papers? Bringing it to school and getting your kids to do it isn’t as far fetched as it sounds. A little time digging through those odds-and-ends can sharpen their visual acuity, teach them the difference between a metal screw and a lock washer, sharpen their sorting skills and help them see how a large task can be accomplished with persistence.