When he's barking in his crate, ignoring is great, because if you go to him, he will learn that's how i get mom's attention.. HOwever if it doesn't stop while ignoring him, what you can try is get a squirt bottle and spray him with water and at the same time, say no. I had to use the squirt bottle with my dog a bit when she was younger
And you didn't mention what type of dog it is, but if it's a breed that is bigger that can tend to be, how to word this, a strong willed dog so to speak.. ie shephard, rott, when he is showing you his teeth he is always trying to take alpha position over you, so you need to correct this now before it gets too late, problem is with a puppy you have to be careful with correcting, and i'm actually not sure how to handle that one, but maybe you can ask the trainer when you train him.
good luck..