Final Post:

Question: 
Why does letting a small ball drop on top of a larger ball make such a dramatic difference in bounce?

Objectives: 
The CA Physics standards that relate to this question are:

d. That when one object exerts a force on a second object, the second object always exerts a force of equal magnitude and in the opposite direction (Newton's third law).

e. The relationship between the universal law of gravitation and the effect of gravity on an object at the surface of Earth.

f. Applying a force to an object perpendicular to the direction of its motion causes the object to change direction but not speed.

h. Newton's laws are not exact but provide very good approximations unless an object is moving close to the speed of light or is small enough that quantum effects are important.

My Conclusion: 
The reason that a small ball dropping on top of a larger ball is so much higher then when you just just drop the small ball normally is because when both balls are dropped, the momentum from the larger ball
gets transferred to the smaller ball causing the much higher bounce. Since the mass of the larger ball is more then the smaller ball, its force upon the smaller ball is much greater then it's own force.