I think spending more time in his crate is creating more energy for him to burn...the family has become a excellent chew toy whenever he's out. He does need to learn to have a soft mouth.
My boy was very mouthy as a pup. I tried the yelping thing...yeah, that just got him more excited. lol
I just wore him out (playing and we were enrolled in obedience classes as well) and gave him things he could chew on (deer antler, raw bone, etc.).
Whenever he became over the top with the mouthing - game over. I walked away from him and did not engage him until he calmed down again.
Putting him in his crate is fine at times but you have to work though it with him.
Good luck - it does pass!