Subject: Wouldn't expansion and contraction help me out?

For my science fair project I am doing "Does temperature affect how high a 
ball bounces?" I did my expiriment (bouncing a softball, baseball, 
rubberball, golf 
ball, and tennis ball from 48 inches and  measuring how high each bounces. 
I did 
this in several different conditions either after the balls had been in 
the freezer, 
fridge, heated stove, room temp.)I did this 3 times and my results made no 
sense. 
I thought when balls were heated they would bounce the highest due to 
expansion and 
that when balls were frozen they would bounce lower due to contraction, 
but my results 
really don't support that, or any type of pattern (Yes, I did do the 
expiriment 3 
times, but none of the results show a pattern at all really this is the 
most recent 
time I tried it, and I was most careful to do everything correctly and get 
the right 
measurments this time):	  
 
Frozen- 

Baseball-16 
Softball-21 
Golfball-35 
Rubberball-37 
Tennisball-10 
  
Fridge- 

Baseball-15 
Softball-19 
Golfball- 39 
Rubberball- 36 
Tennisball- 24 

Room Temp-  
 
Baseball-15 
Softball-19 
Golfball-39 
Rubberball-36 
Tennisball-27 
  
Heated- 
 
Baseball-17 
Softball-19 
Golfball-37 
Rubberball-34 
Tennisball-28 

  Please help me make sense of this and provide me with any information 
possible. 
Thank you very much. 
 

Re: Wouldn't expansion and contraction help me out?