Quoted from swampfire:

You advance these by hitting the 3 stationary targets for 6, 7 and 8, and collect the value when that ball is the next shot (it's flashing). A great way to hustle someone is to let them think they're beating you, while you max out those targets. Then collect 50-50-100 by hitting 6-7-8. One of my favorite things about this game.

Quoted from djreddog:

I have an issue with drop target #5. When I first got the game, all drops worked. After about a week or so the coil on drop target #5 burnt up. When it burnt up, and to prevent other damage, we simply cut the single "grey" wire to the coil. So after several weeks, I finally bought a new coil and replaced it today. The coil works, as I confirmed this by running an alligator clip from the ground wire to the single wire lug on the coil and it fires. However, when the game resets all the drops, #5 will not reset. I've doubled checked all wiring and can't seem to find anything wrong that would prevent the target from resetting. Any thoughts on what I should look for?