well i take mine out for a hack using the roller skate, tail dragging method.......
they love it. then i throw sticks at them and they have to rear up and catch them in their mouths in the school once we get home.
do they wear the roller skates or do you. I thought they might be an improvement on old macs. also, surely is you are throwing sticks and they are catching them, you now have to take it to the next stage and have them drop them at your feet. Only then you will know they trust you enough to give you their stick!