Students' scientific models of momentum

A group of 7 grade ten students of The Demonstration School of Ramkhamhaeng University (Secondary Level) had been taught by modeling-centered instruction sequence (MCIS) on the topic of momentum for 2 hours. The students participated in nine learning steps of MCIS; (1) anchoring phenomena and central question, (2) construct an initial model, (3) empirical investigations, (4) evaluate and revise the initial model, (5) introduce scientific ideal and simulations, (6) evaluate and revise the model, (7) peer evaluation, (8) construct a consensus model, and (9) use the model to predict or explain. Then, we focused on evaluating their ability to create scientific model during the steps 6, 7, 8, and 9. The students created a scientific model was that was analyzed by separate evaluation criteria. The results show that there are four model types that students used to explain momentum. (1) Pictorial Representation, the student drew and provided symbols ((p) over right arrow, m, (v) over right arrow) and images related to momentum. (2) Experimental Representation, they showed scientific concept during the experimental stage by painting and providing symbols and messages related to momentum. (3) Mathematical Representation, they presented some understand of relationship between mathematical variables such as (p) over right arrow = m (v) over right arrow, (p) over right arrow = momentum (kg center dot m/s), m = mass (kg), (v) over right arrow = speed (m/s). (4) Conceptual Representation, students concluded that amount of momentum depend an object is moving and fast an object is moving. If the velocity is stable, then the momentum of the object depends mainly on its mass.