In developing a concept of the universe at the elementary level many learning aids are utilized. Visual presentations, direct observations, experimentations and critical reading accompanied by discussions serve to enhance a child's understanding of a concept. Moreover, it is apparent that all elementary school children do not arrive at the same level of understanding of scientific phenomena. There are many children who do not respond effectively to experimentation and critical reading and thus must rely on direct observations and visual presentation in arriving at a lower level of conceptual development. Other children who are more sophisticated may understand the orderliness of scientific phenomena and display knowledge of the vastness and complexities of our universe. Branley (1), Sheckles (13), and Vinacke (14) have pointed out that differentiation and gradual progression take place in concept development as one matures. Further credence is given to this belief by Russell (12) who states that "concept development seems to move along a continuum from simple to complex, from concrete to abstract, from undifferentiated to differentiated, from discrete to organized, from egocentric to more social."
Bush, B. O., & Govatos, L. A. (1963). Developing Elementary Science Concepts by an Individualized Approach. Reading Horizons, 3 (2). Retrieved from https://scholarworks.wmich.edu/reading_horizons/vol3/iss2/4