In the snowball fight, be sure to tap and hold your players to charge up a throw. It's better to toss one accurate "Perfect" shot than three "Good" ones.
Try to pass the puck around as much as possible in Ice Hockey - it's the only hope you'll have of changing your player's positions on the ice.
For Curling, try to aim just to the left or right of the center circle. If you leave your rocks in the middle, the AI opponent will have no trouble knocking them out of bounds.