Shepherd- I need advice

Hi everyone,
I rescued a 1 year old German Shepherd last year (apparently he lived with a Pit Bull). When on walks, he goes absolutely nuts when we encounter other dogs (I should also mention that he is 110 lbs). He lunges and tries his best to get at them while barking his head off the whole time. He loves other dogs and wants to play. Yes, I am sure...his tail is wagging and he gets along with other dogs very well. The problem is that I can't control him as he is so focused on getting across the street to visit. He actually pulled me right off my feet last week. Given his size and the barking, he scares people half to death, particularly those walking little dogs, who are probably convinced that he will tear their dog to bits. I use a gentle leader on him which works well with heeling but seems useless when trying to control him once he spots another potential playmate. Any ideas?

You can try to distract him, but I doubt you'll have much success. They're very single minded when it comes to anything they're passionately fond of. One of my Shepherds, Big, just completely lost composure around little kids - even babies.

Your best bet is probably a training/obedience class with other dogs. And don't let anyone tell you an adult dog won't do well in obedience class. Not true! I took my first GSD, Purdue, to one when he was 5 years old, and he graduated at the top of the class, with an instructor who actually announced that she intensely disliked GSDs!