Have you ever seen a Click Stick?
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If you know about clicker training, that's what it is. If you've never used the clicker before, you will have to 'charge' it first. So click, treat. Click, treat. Do this over and over again for about 15-20 times. Start letting the dogs head turn away and then click, and if he immediately turns back towards you (after hearing the click), then he understands that a click means a treat.
The purpose of a click stick is used for many things, but walking is one. Teach him to 'target' the end of the stick. So every time his nose touches it, you click and treat. Then when you go on your walks, point out the stick so that Teddy is moving forward in order to touch the stick, and he gets a treat.
If you don't want to get a stick, you can also use your hand. Teach him the 'touch' command and do the same thing... every time he touches your hand, he gets a treat. It will be a bit more bending over on the walk, but encourage him to touch your hand, and move forward.
He sounds pretty smart. They pick up on things fast. He stopped walking, you picked him up, carried him home... he's thinking "oh, I can try that again!" He's training YOU very well
hehe. He should pick up soon enough, just keep trying. Have patience, and lots of food and praise.