While not all Physics courses discuss inclined plane problems, those that do will appreciate this Concept Builder. This Concept Builder has three variations of inclined plane problems. Each physical situation involves the acceleration of an object along an inclined plane. Students must analyze the situation, determining the parallel- and perpendicular-components of the gravity force (mass is stated), the normal force, the friction force (in Master and Wizard Levels), the net force, and the acceleration. They must also identify that quantity associated with the given information. The numerical values provided to students will vary from session to session and from student to student as they are randomly generated. 

This Concept Builder consists of three difficulty levels. Each level includes two situtations that must be analyzed. A free-body diagram and a short description is provided. Two or more numerical values (for example, mass, incline angle, and friction information) are provided. Students must identify the values of up to 9 quantities (7 in Apprentice level and 8 in Master level). A few of the values are stated in the provided description. The others must be calculated from an understanding of  the relationships implicit to the situation. It is not necessary to start with the Apprentice Level or to finish with the Wizard Level. The activity was designed such that classrooms jump in and jump out at the locations that are most appropriate to them. We recommend that teachers view the Questions or do the Concept Builder in order to make judgements about what works best for their specific classes.

The three difficulty levels are differentiated as follows:

• Apprentice Difficulty Level Questions 1-2: Analyze a problem involving a force applied at an angle to the horizontal to cause a horizontal acceleration. No friction.
• Master DifficultyLevel Questions 3-4: Analyze a problem involving a force applied at an angle to the horizontal to cause a horizontal acceleration. Friction value is given.
• Wizard Difficulty Level Questions 5-6: Analyze a problem involving a force applied at an angle to the horizontal to cause a horizontal acceleration. Coefficient of friction is given.

In order to complete a difficulty level, a student must successfully analyze both situations of that level. A successful analysis involves determining all the correct information requested - like the parallel- and perpendicular-components of the gravity force, the normal force, the friction force, the net force, and the acceleration. A student can enter values one blank at a time and use the Check Answers button to check. Feedback will be immediate and correct response cannot be changed thereafter. Incorrect responses can be corrected until they are correct. There is no penalty for misses or difficulty (other than the extra time and frustration that can be associated with it). When both analyses are correct, the student is returned to the Main Menu and (if logged in as a Task Tracker user) the Trophy for that difficulty level is displayed.

The most valuable (and most overlooked) aspect of this concept-building activity is the Help Me! feature. Each situation is accompanied by a Help page that discusses in detail the specifics of the situation. Formulas, tips, suggestions, etc. are provided. 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.