Do you have more information on the scent games? I think that would be good for them, and then should I only play with one dog at a time and put the other one in a kennel or in another room, or can both play?
I detailed a couple of the scent games in the article I linked to below:
http://sheltie-hair.blogspot.com/2008/10/creating-mental-balance-in-sheltie.html
Once both dogs know the rules of the games and how to play, then they can play together for the "hide and seek" type games. The scented containers I would play individually.
Right now I am having a little bit of a harder time training with the clicker, as both dogs are around, so I have to lock one up somewhere so he or she does not hear the click. Someone told me that they have a 'deluxe' clicker now, that makes different tone clicks, so you use one tone with one dog and another with the other. Have you heard of this? Do you think it would work?
Clicker with two dogs at once is a little bit tricky, but there are way around it. There is a Clicker+ that has different sounds. I considered purchasing one of these, but at the rate that I go through clickers I didn't want to risk losing or breaking this more expensive one!

Instead, I will either put one dog away when I am using the clicker with the other, or I will work one dog on "non-clicker" tricks while I work the other with the clicker. For example, if I am working both dogs at once, I will put one dog in a down-stay or a sit-stay and work with the other dog with the clicker. I find this game very helpful in letting the dog know that the click doesn't serve as a "release". So the dog in the stay is required to ignore the clicker because it isn't intended for them. I will work this way for about 5-10 minutes, then switch dogs. The dog that was in the stay is released for clicker work and the dog that was working with the clicker is put into a stay. I personally do not use the clicker for duration activities (like stays) so will reward periodically through the stay without clicking first. I only use the clicker for initial training of a new task, cleaning up an old task, or adding speed or response.
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