I used to have this with my 2 previous spaniels as they got SO excited when going out. To be honest, I think most dogs get excited when they go out though. It got to the point when I found it difficult to even get their leads on as they were dancing around so much.
One day I got so exasperated with them that I just threw their leads on the floor and just stood there with my arms crossed. They immediately shut up and looked at me with amazement, what was I doing?
Then every time I picked the leads up and they got excited I threw them on the floor again. They soon learnt that if they got excited it got them nowhere. You do have to be consistent though, any excitement or noise and the lead gets put down.
This worked for me, hope it does for you