10 month Lab Jumping on people

Question
We have a 11 month old lab (Lucy) and a 10 month old lab (Ricky).They have been to puppy school and did fine. They are housebroken and only chew on their toys. We cannot get Ricky to stop jumping up on everyone he meets. We consistently tell him "off." But we still have the problem after 3 months of trying. We never yell, but our voice is firm. He is just not getting it. Lucy caught on right away. Any suggestions?

Answer
Tell him off another thousand times.  Add a correction.  Some dogs are more strong willed than others.  I frequently see ''Free to good home 7-8 month old male Lab''.  People give up on them.  Some of them are not easy dogs.  Consistently is very important in correcting jumping and other problems.  Quickly correcting him each and every time he jumps on somebody is very important.  Something bad has to happen each time.  People are successful with a number of different things.  One of the most gentle is to grab his front paws and hold him up.  The traditional knee to the chest or step on his paws work well too.  In each case apply ''Bad dog, its name off!'' in a firm, but not loud voice.  Go ahead with it even if he is too quick to add a physical correction.