My 1 yr old foster lab has started frustration barking and i suspect its because he needs more stimulation. He will be starting assistance dog training in a couple of months but until then I would like some ideas of games we can play that are cheap and will get his brain working. We already play hide the bonio, hide and seek with the kids, and hiding a treat under one of several beakers for him to find. I have been looking at the Nina Ottosson puzzles and think they look great but I really can't justify spending that much money. Is there any cheaper alternatives out there?