His ears may not stand... Depends on his genetic makeup.
Boston puppies ears will begin to go up at about 3 months of age or sometimes sooner if they are going to go up at all. They will then curl back or flop forward at the tips and go up and down until they are about 6 - 8 months old.
While the puppies are losing thier puppy teeth and gaining adult teeth thier ears will go up down as the teeth and growing bones are taking alot of the calcium they need. During this time, if the puppy's ears do not look strong enough to stand you can tape them up to help support the cartiledge and help it stiffen in an upright position.
here are a couple of links that explain how to tape the ears:
http://www.boston-terriers.com/ears.htm
http://www.bostonterrierclubofameric...rom_Betsy.html (scroll to bottom of page)
Jeannie Thomason