How does the weight of a soccer ball affect the game?

Answer 1

well... a ball with too much air pressure is harder, therefore creating a more powerful kick (and more hurt toesies) and a ball with too little air pressure can form to your foot and be of no use at all to you, unless you want to deal with a very big nuisance. BUT one with the just right amount of air pressure wont hurt your toes and result in a high-power kick.

Answer 2

Basically, if the ball is too heavy then more energy is required, and it gets hard to control how far/where the ball goes. Same things with too small, except instead of being too heavy if the ball's smaller, you can over-hit it.

(see also the related link below)