[Orion.DeYoe]

So it seems like there aren't many simple ideas that are foolproof for real-time scoring. The weight sensors seemed like a good idea but I think the biggest problem is that the discs not only exert force on the bottom of the bin but also on the sides (which leads to the settling problem).
In my opinion they should use through-beam sensors running top to bottom in the goal . They would have the sensors (receiver on top and emitter on bottom or something like that) spaced out evenly in a row right in the opening of the goal with no gaps big enough for a disc to slip by without triggering a sensor. Then they would have a duplicate set spaced 2-3 inches farther inside the goal than the first set.
This would allow them to not only sense the discs presence in the opening of the goal but also it's direction of flight. If the first set is triggered first and the second next then the disc is entering. If the back sensors are triggered first then the disc is bouncing back out. You might actually have to look at the other end of the sensor spike just in case of a disc not going all the way past the sensors. If the first sensor turns off before the second then the disc has gone in whereas if the second sensor turns off first then the disc was leaving the goal.