We typically are not teaching students who are taking their first Science class. Most the students we teach have taken one or more science classes at some time during their school career. And they have likely been exposed to the idea of the scientific method. They probably have learned about variables and experimentation. And often teachers of Physics presume that such concepts are well-understood and as such they give very little time to developing such ideas. And there are other teachers who spend a considerable amount of time (maybe an initial unit or portion of a unit) discussing variables, graphs, relationships, and more. Wherever you fall upon this spectrum, you will find this Concept Builder to be a quick means of assessing student understanding of topics associated with conducting a controlled experiment.

Each of the three activities in this Concept Builder have a slightly different slant to it. The goal of the collection of three activities is for students to understand the connection between an experiment's purpose, the variables that will be under study, the basic manner in which they will be controlled and manipulated, and the proper means fo plotting the data on an x-y graph. The Concept Builder was intended as an in-class activity. Teachers are encouraged to preview the activity (or view the Questions in the separate file) in order to judge which activities would be most appropriate for their students. Our summary of the three activities is as follows:
 

• Purpose and Variables: Questions 1-4 ... Given a Purpose statement for an experiment, learners identify the dependent and independent variables. 
• Experimental Design: Questions 5-8 ... Given a Purpose statement for an experiment, learners identify the best procedural design from among a choice of four.
• Data Representations: Questions 9-12 ... Given a description of the purpose, learners identify the dependent and independent variables and the best graphical representation of the data.

In order to complete an activity, a student must correctly analyze each question in that activity. If a student's analysis is incorrect, then the student will have to correctly analyze the same or very similar question twice in order to successfully complete the activity. This approach provides the student extra practice on questions for which they exhibited difficulty. As a student progresses through a level, a system of stars and other indicators are used to indicate progress on the level. A star is an indicator of correctly analyzing the question. Once a star is earned, that question is removed from the que of questions to be analyzed. Each situation is color-coded with either a yellow or a red box. A red box indicates that the student has incorrectly analyzed the question and will have to correctly analyze it twice before earning a star. A yellow box is an indicator that the question must be correctly analyzed one time in order to earn a star. Once every question at a level has been analyzed, the student earns a Trophy which is displayed on the Main Menu. This system of stars and trophies allows a teacher to easily check-off student progress or offer credit for completing assigned levels.

The most valuable (and most overlooked) aspect of this Concept Builder is the Help Me! feature. Each question group is accompanied by a Help page that discusses the specifics of the question. This Help feature transforms the activity from a question-answering activity into a concept-building activity. The student who takes the time to use the Help pages can be transformed from a guesser to a learner and from an unsure student to a confident student. The "meat and potatoes" of the Help pages are in the sections titled "How to Think About This Situation:" Students need to be encouraged by teachers to use the Help Me! button and to read this section of the page. A student that takes time to reflect upon how they are answering the question and how an expert would think about the situation can transform their naivete into expertise. 

 

 

There are very few resources at The Physics Classroom website that pertain to the topic of experimentation and variables. What little discussion that is present is treated as more of an application in the understanding of other topics. Teachers will find that the most-related supports for the topic of variables and experiments are the other Concept Builders found in this same chapter of the Concept Builders section.