These blog posts detailed how I taught Iona the concept of water hides starting easy and slowly increasing the difficulty. It is important for me to remember that if she shows confusion with a new skill, it is probably because I skipped or rushed a step in training it.
I lost the video for one of the searches in this progression. Basically, after the last bunch of searches, I practiced the shell game with the screens on top of the containers. This was a pretty important step because with the screens, the hide is very inaccessible.
After she succesfully searched through three boxes (one hot and two cold). I added one more hot box and another cold box and then switched them up with each run. It looked something like this.