Leave it and take it
Benefits: Your dog stops pursuing his interest leaves it and looks to you! YES! From garbage on the street, other dogs, other dogs balls even squirrels and and other animals. Take it - your dog learns only to take items from from hand when you say take it.
1. Hide a kibbles in both of your fists. Say "leave it" and let your dog sniff/explore one of your closed fists.
When your dog looks away from your fist us your marker YES and feed your dog kibble from your other hand. Repeat this until your dog no longer tries to get your dog kibble from your fist. At this point you will keep repeating the exercise however you will now mark and reward when you dog makes eye contact with you.
Show your dog the kibble and place it on the ground and cover it with your hand. Say "leave it" and let your dog sniff/explore the covered kibble and repeat Leave it until he looks away and user your marker YES and feed your dog the kibble from your treat pouch (the hand) that is not covering the kibble and repeat until the dog is making eye contact with you when you say leave it.
Show your dog the kibble and place it on the ground uncovered. Say "leave it" at this point your dog should be stopping and making direct eye contact with you with the command leave it. Use your marker YES and feed your dog the kibble from your treat pouch (the hand)
Put your dog in a sit and show your dog the kibble in your hand and toss it to the side of the dog. Say "leave it" use your marker YES and feed your dog the kibble from your treat pouch (the hand) Repeat this throwing the kibble in different spots around including in front and behind of them. Work up to tossing multiple kibbles.
Changing items once your dog is successfully completing step 3 (saying leave it with exposed kibble and making eye contact with you replace the kibble with other desired items. If you have a puppy use your socks, slippers, shoes, or personal item that they love to sneak and steal. This is also the time to start using their toys. Start with low value toys and work up to a ball tug toy (high value depending on the dog). At this point you will use the toy but the same method as step one and you should be able to quickly advance to step three.
Curb your dogs impulse to chase another dogs ball or sticks. If your dog is ball crazy practice this at baseball and soccer fields or basketball courts keep your dog at a distance that they are interested and then ask them to leave it, mark and reward and get closer, closer and closer.
Throw the stick or ball and ask your dog to leave it and then use your release word for them to fetch the ball or stick.
Use the command not the tone. Often we say leave it in a stern voice and forget the mark and reward the behaviour. Your command should be spoken in a natural voice.