Models and Modeling in the High School Chemistry Classroom. Larry Dukerich Modeling Instruction Arizona State University. Traditional Instruction. Presumes two kinds of knowledge: Facts and ideas - things packaged into words and distributed to students.
Arizona State University
What does it mean when students can solve quantitative problems, but cannot answer the following?
Nitrogen gas and hydrogen gas react to form ammonia gas by the reaction N2 + 3 H2 2 NH3The box at right shows a mixture of nitrogen and hydrogen molecules before the reaction begins.
Which of the boxes below correctly shows what the reaction mixture would look like after the reaction was complete?
Before we investigate the inner workings of the atom, let’s first make sure they really believe in atoms.
Gas Diffusion: Where’s The Air?
The Continuous Model of Matter
Why teach a model of the inner workings of the atom without examining any of the evidence?
Because students have trouble relating microscopic and macroscopic views, we start our discussion with the atom and bypass the traditional historical approach taken by many texts. (This is not to say that we do not value the study of the history of chemistry; in fact, we believe that history helps the material come alive.) Pictures from scanning tunneling microscopes can now “show” us atoms. Therefore, we begin with “We believe in atoms because we can see them.”
“Teaching Tip” from World of Chemistry, Zumdahl, Zumdahl, DeCoste, McDougall Littell, 2007
Models are representations of structure in a physical system or process
Examine matter from outside-in instead of from inside-out
181 kJ + N2 + O2 ––> 2 NO
constructivist vs transmissionist
cooperative inquiry vs lecture/demonstration
student-centered vs teacher-centered
active engagement vs passive reception
student activity vs teacher demonstration
student articulation vs teacher presentation
lab-based vs textbook-based