Cut apples crosswise into 1/4" slices to form circles. Discard or eat top and bottom of apple. Spread two circles with peanut butter. Stick four toothpicks, equal distances apart, around the edge of of apple circle, peanut butter side up. Top with second apple circle, peanut butter side up, and secure to tops of toothpicks to form a carousel. Stand four teddy grahams in the peanut butter between the toothpicks. Place a gummi bear in the center of the carousel roof. Repeat to make a second carousel. Serve, being careful with toothpicks.