Science Practice: Developing and Using Models

A Polystyrene Model of Polystyrene Tacticity

Thin sheets of polystyrene can be patterned with permanent markers to represent repeating units of the polymer and then shrunk down in size using heat. The shrunken models of the repeating units can be connected with a string and then flipped into positions to demonstrate different types of polymer tacticity.

Analogy Experiment—Projectile Pennies with Rutherford

Atomic theory is a common topic throughout any introductory chemistry course. It is likely that Rutherford’s gold foil experiment gets at least some attention in your course. This simple activity gives students an opportunity to replicate Rutherford’s experiment through an analogy experiment that may allow for easier conceptualization of the experiment itself and provide additional support for model development.

Real vs Ideal - Do Students "Get It"?

Allowing students to confront the failure of a model and then helping them construct a new or slightly modified model to account for new observations is at the heart of the process of science. Ben Meacham shares one approach that can be deployed with a variation of depth, making it attainable for anyone learning about chemistry.

Lesson to determine the relationships between acid strength, Ka, pH, Molarity, and percent ionization

After teaching the concepts and calculations for acid and base strength, concentration, percent ionization, and pH I noticed many of my students were struggling to make meaningful connections between these calculations.This lesson was created to strengthen the understanding of the relationships between these concepts and skills.

Kasi: A Multi-Sensory Modeling System

Doug Ragan has been working with the Alchemie team -- founded by a former chemistry teacher, Julia Winter -- for a number of years. They have been working over the last year on a new project, named Kasi, which delivers sound-based feedback to students as they learn with tactile pieces on a magnetic whiteboard. The goal is to build an accessible learning system that helps ALL students learn, and is particularly important for those with visual impairments.