Toys and games can be a very useful tools to help train a service dog. Different kinds of toys can be used for different functions.

There are two kinds of toys: active toys are objects that allow interaction between you and your dog. Tug toys, balls, toys with squeakers fit this definition.  Passive toys that your dog can play calmly with by herself like a food-filled rubber toy that doesn't roll around, chew bones or stuffed toys can be useful when conditioning calmer behaviours like a settle or stay on your mat.  

Active Toys and Games

Active toys and games can be used to motivate a dog for behaviors that require a higher energy level (like tugging doors open) and for alternating with behaviors that are stationary after they have been trained. They are useful to release stress and give the dog a break when taken outdoors between periods of work. It helps when indoors if the toy can be controlled by you. So a ball on a rope or a brings attached to the dogs harness is ideal. The toy will not be able to mover so the dog won't go chasing down a slippery hallway to get it in public. In general, during the training phase for behaviours and tasks, active toys are best used at home or in the training rooms and outdoors. Once the dog dog has the desired enthusiasm and can do the behaviour or task, then you can train them in public without the use of toys. 

Passive Toys
Passive toys can be used to teach the dog to entertain herself (add duration) while in a settle. They can help calm a dog down or self-soothe after an active behaviour or task such as finding a helper, actively detecting a scent or walking quickly for a long distance. The activity of chewing and licking helps most dogs calm down.

It is important that you carefully choose which games to pair with which behaviors and situations. For example, rough or rousing toy play, tossing treats or hide and seek is not appropriate in a retail store (unless you are training your dog to find a person as a task).

Pairing Active Games with Calm Games

How you use the active toys and games is important. When pairing active toys and games with calm activities make sure the active games come first. Always end on a calm activity.  This ensures classical conditioning is working in your favour to teach the dog to calm down after activity. This order prevents inadvertently conditioning your dog to be hyped when doing the calm behavior. The anticipation of toy or game after a settled behaviour for example, causes the dog to be ready to play during the calm period. This can cause whining, muscle tightness and other undesired behaviours while waiting for the play to happen. 

You can use the choice of toy you use to help your dog understand that some environments require calm behavior while others can be playful. Outdoors use active toys and play, and indoors, especially in quiet places, use passive toys. If your dog is resting under your chair at work, or settling for long periods at school, taking frequent breaks to do active play outside is a great use of it. 

Some people only use play at home if their dog is easily aroused during active games. Others avoid uses toys while the dog is vested and at work.  

Active toy play and games is also great for building a bond with a dog that loves activity.