Crates are a great housetraining aid! My puppy was completely housetrained by 20 weeks! NEVER use a crate as punishment or isolation (puppy should sleep in the same room as you). Feed & give chews in crate for positive association.
10 Dog-Training Tricks Straight From the Dog Whisperer
Pupy Training Treats - Eye Makeup - Use Nudges dog treats from to teach your dog how to ring a bell to let you know when he has to go outside! - Ten Different Ways of Eye Makeup - How to train a puppy?