The style of stop-motion animation is extremely flexible. If the objects are being moved instead of being animated or manipulated it means that they can go anywhere within 2D space. The simple 2D drawings themselves are childlike in appearance but also in essence as they represent the most basic form of animation.
Because of the physical involvement of having to use ones hands and fingertips to move every item bit by bit, frame by frame, it is like child's play. The animators hands set the tone of the film.
Everything was done in a way that let the children steer the direction of the film by giving them open questions they were free to interpret as well as letting them express their ideas about the subject through art. The film depended entirely on their responses and the activities were carried out in a way that ensured they were comfortable and happy during the process.
The initial audience for this film was children and the different animations, style and colours should reflect that. The simplicity of the design, though technically complex, should appeal to children and adults alike - or might at least awaken the childlike imagination inside all of us.