The Green is a great beginner foraging toy. This is the doggy version of the feline "Catch" toy. Because it is larger, it holds more volume for multiple cat households and provides a slightly increased challenge as the interior portion of the puzzle is harder to reach.
If you want to increase the challenge even further add a foraging ping pong ball from Fundamentally Feline. Simply fill ping pong ball and drop it into one of the sections. The cat has to spin the ball to get the food to drop into the Green and then extract it from the maze with their paw. Yes, cats really do get this skilled at foraging!