For a certain type of kid, the urge to take things apart and see what’s going on in there can be almost overwhelming. (The primal urge to tinker, if you will.) If both you and your kid are natural tinkerers, taking on basic mechanical repairs together can be a great way to bond and keep household appliances working smoothly.
As with all projects, the secret to having fun is to choose something your kid actually cares about. If they love cars, learning how to replace headlights, spark plugs, or change the oil will be interesting and undeniably useful down the line. If they’re really into baking and you own a KitchenAid mixer, set aside a weekend to take that sucker apart, clean the gears, and replace the grease. If they just like dismantling stuff, go hunting in the basement, attic, or Goodwill donation pile for old items nobody will miss—then destroy it methodically enough to see how it works. Even if you don’t end up fixing anything, you’ll have tons of fun.