Using PhET simulations to replace real equipment in lab – Circuit Construction Kit

Compiled by Sam McKagan, based on material from the PhET Team
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This material is replicated on a number of sites as part of the SERC Pedagogic Service Project

Summary

Real Circuit and Circuit Construction Kit simulation

Labs and tutorials that use equipment such as circuits can be modified to use PhET simulations instead. Research shows that substituting the PhET Circuit Construction Kit simulation for real equipment in a variety of contexts leads to improved conceptual learning in the best cases, and the same conceptual learning in the worst cases. There are many advantages to using PhET simulations over real equipment: They are easy to use, so students can play around and modify the experiment quickly and easily without fear of breaking the equipment. They have productive constraints to focus attention on the most important aspects of the experiment (e.g. bulb brightness and current flow) rather than on irrelevant aspects (e.g. wire color and length). Finally, if real equipment is not available, PhET simulations provide the opportunity to do multiple experiments with a single piece of equipment: a computer.


Learning Goals

There are many possible goals for laboratories, including conceptual learning, laboratory skills, scientific thinking skills, and troubleshooting equipment. Substituting PhET simulations for real equipment in laboratories can improve conceptual learning by providing explicit visual models, by providing constraints that eliminate distractions and allow students to focus on only the important features, and by providing a safe environment for students to play without worrying about breaking the equipment. PhET simulations are likely to be less effective for achieving goals such as laboratory skills and troubleshooting equipment. On the other hand, in one study, students who had completed a lab with the Circuit Construction Kit simulation were able to put together circuits with real equipment faster than students who had completed a similar lab with real equipment.

Context for Use

PhET simulations can be used to replace real equipment in laboratories or in recitations in which students work in small groups on hands-on tutorials like the University of Washington Tutorials in Introductory Physics. PhET simulations can be used in place of many different kinds of equipment including circuits, magnets, pendulums, lenses, masses and springs, ripple tanks, standing wave generators, or even a photoelectric effect apparatus.

Description and Teaching Materials

The specific laboratories used in the PhET research studies on replacing real equipment with a simulation in circuits labs are available from the PhET activities database:
DC circuits lab with real equipment and CCK
Current in DC Circuits
However, the labs themselves, while somewhat inquiry-based, are not exceptional or developed based on research. The main point of these studies is that simulations can lead to improved learning even in an ordinary lab that is not carefully designed. Simulations can be incorporated into labs you already teach.

The tutorial study used tutorials from the University of Washington:
Tutorials in Introductory Physics
These tutorials have been carefully constructed based on research into student understanding of physics. They guide the students through the process of constructing a model based on observations. One might think that these tutorials are incompatible with the Circuit Construction Kit simulation because the simulation reveals too much of the model by showing the electrons and therefore cuts short students' process of constructing the model for themselves. However, research shows that using the simulation (with or without showing the electrons) leads to as much conceptual learning as using real equipment.

The PhET team has developed an alternative tutorial which attempts to take advantage of the unique characteristics of the simulation, rather than just inserting it into a tutorial designed for use with real equipment:
Potential Difference in Circuits

Teaching Notes and Tips

PhET simulations can be incorporated into any kind of lab or tutorial that uses real equipment with a corresponding simulation. The most straightforward way to do this is to simply substitute the simulation for the equipment without changing the lab or tutorial at all. This is easy to do and research shows that it works well. On the other hand, the simulations have many unique and productive features that real equipment does not share, and it is also possible to make significant modifications to labs and tutorials to take advantage of the particular features of simulations. While simulations can certainly be incorporated into cookbook labs, research shows that guided-inquiry activities are more productive for conceptual learning. To get started developing effective labs that use the simulations, take a look at the PhET Activity Guidelines. To find labs that others have developed, go to the PhET Activities Database and do a search setting "type" to "lab." Look for the PhET logo to find activities developed by the PhET Team, and look for a gold star to find activities that follow the PhET Activity Guidelines.

Assessment

Research shows that substituting the PhET Circuit Construction Kit simulation for real equipment in a variety of contexts leads to improved conceptual learning in the best cases, and the same conceptual learning in the worst cases.

Members of the PhET team (Finkelstein et al. 2004, 2005) did a research study in which they replaced the equipment in a DC circuits lab with the Circuit Construction Kit simulation for half the lab sections in an introductory college physics course. They found that students who used the simulation were able to build a real circuit in less time than students who used the real equipment, and performed better on a challenge question immediately following the laboratory and on final exam questions on DC circuits two months later.

In another study, researchers (Keller et al. 2005) replaced the equipment in an inquiry-based tutorial from Tutorials in Introductory Physics with the Circuit Construction Kit simulation for half the recitations sections. They found that students using the simulations performed slightly better or about the same. This study shows that simulations can be effective not just in traditional labs, but in carefully researched inquiry-based curricula.

In another study, researchers (Keller et al. 2006) replaced the equipment in a lecture demo on circuits with the Circuit Construction Kit simulation in one section of a large lecture introductory physics class. They found that the students who saw the demonstration with the simulation performed significantly better on a concepTest than the students who saw the demonstration with the real equipment. They speculated that the improved performance was due to the model of current flow given by the moving electrons in the simulation, which is not apparent when viewing real circuits. To test this hypothesis, they created a version of the simulation that does not show electrons and did a follow-up study in lab: After completing one circuits lab with real equipment, all students in a large lecture course completed their second circuits lab using the simulation, half using the version with electrons and half without. Both groups performed equally on measures of conceptual understanding, and both groups rated the simulation lab as significantly more enjoyable and more useful for their learning than any other lab in the course. However, the students who used the simulation without the electrons rated it as significantly more enjoyable and more useful for their learning than did the students who used the simulation with the electrons. The researchers speculate that the students using the simulation with electrons found the lab less interesting because the electrons made the current model so apparent that they took away some of the challenge.

References and Resources

These papers discuss research showing that students learn as well or better in a laboratory with the real equipment replaced by the Circuit Construction Kit simulation:

This paper discusses research showing that students learn just as well when using Tutorials in Introductory Physics with the real equipment replaced by the Circuit Construction Kit simulation: