I have a 17month old border collie and I'm beginning to despair over her ever being able to walk normally on a lead. 
She's done puppy training and her bronze obedience thing so she knows the theory but she is just so excited when we leave the house that walking to school is a nightmare! She has 2 hour long runs a day but I usually drive to a field and let her off.
I've tried a harness but that doesn't seem to make much difference and she managed to get her paw stuck in a halti while in the shop so that was a non-starter.
Oh and she's started to pull after/chase cars again which I thought she'd grown out of.
Do I take her back to training classes, even though when she's there she walks perfectly? The walk to school is very distracting for her with traffic and dc on scooters but unfortunately this is the only time I have to take her. The dc prefer to walk rather than taking the car (which is easier for me with the dog). I let her off on the field for a good run then we walk back and she's exactly the same, pulling my arm off!
Please tell me they just grow out of it eventually!