As you progress through the game, your pup will get stronger, and be able to take longer walks. These walks can lead you to the park to practice for disk competitions, to the gym to train for an agility competition, or even to a surprise, such as another dog or a present.
Park There are two parks, one with many other dogs and one that is almost always empty. The one populated with other dogs is great when you want your Nintendog to be able to play with its kind. Its great when you don't want to train your puppy, but instead just let it hang out. The empty one is preferred for disk training, as other dogs can prove to be a distraction. The best throw, easiest for your Nintendog to catch, is straight forward and high in the air to encourage a jumping catch. Be sure to call your puppy back immediately after they catch it so that they will make a habit of it. All of this is important in disk competitions as it will help you earn more points.
Gym The gym is there so that you can take your Nintendog through the agility course before a trial, to make sure it is ready for the competition. Never sign up for an agility trial without practicing first, or you will undoubtedly lose.
Surprises Sometimes the surprises are marked on the map with little question marks. If that is the case, your Nintendog will immediately run up to it without your help. But if a surprise is not on the map, you'll have to tug your pup's leash to get it to notice the surprise.