Screencast Practice Problems

Students learn how to solve practice problems in physics through videos created by the instructor using cheap and simple screencast technology.

Goals:

  • To help students progress from understanding physics concepts and formulas to knowing how to apply them to real-world problems.
  • To provide students with explanations of concepts from lecture and examples of the proper technique for tackling particular kinds of problems through a medium they can easily view and reference.  

Class: Physics E1bx: Physics II: Electromagnetism, Circuits, Waves, Optics

Introduction/Background: This class is an introduction to electromagnetism, circuits, waves, optics, and sound for students with varying levels of physics preparation. To assist students with weekly practice problems, the instructor created videos documenting approaches to solving the problem using screen capture software. These videos helped to scaffold students up toward solving the homework on their own.

Materials

Computer

Webcam

Tablet & digital pen/stylus (for writing on screen)

Screen capture software, such as Screencast-o-Matic Pro

Procedure:

Preparation

  • Students were provided with weekly practice problems in class and online.
  • After each lecture, students submitted “1-minute papers” that gave teaching staff feedback about which content they understood and which was problematic. Weekly videos therefore were intended to both cover the practice problems and to bolster understanding of content that many students identified as challenging in their feedback.

Creating a Screen Capture Video

  • The instructor used the software Screencast-o-Matic to record his computer screen, and a webcam to capture his face in the corner of the screen as he narrated what he was doing. He used a tablet and digital pen connected to the computer in order to be able to write on the screen while working out problems.
  • The video begins with a greeting to students and reading the practice problem aloud.
  • First, the instructor analyzes the question and points out relevant information that could be used to solve the problem, using a tablet to write, draw, or underline on the screen.
  • Then, he discusses background knowledge that would help with solving the problem, particularly concepts from lecture.  
  • Next, the instructor solves the problem on the screen, demonstrating proper technique for the particular question.
  • Finally, if there are alternate ways of solving the problem, (e.g., using conservation of energy rather than force diagrams) the instructor discusses these as well.
  • Sometimes, the instructor would create supplemental videos explaining only the concepts and formulas for the week, in case students preferred to review just the concepts rather than the concepts and their applications in practice problems together.
  • The instructor asked for feedback from students about the videos during the course. For instance, he learned that many students were watching the videos on their phones, and so increased the thickness of the line drawn by his digital pen so that his work would be easier to see on a small screen.
  • This software could be used live as well. Each week, the instructor held online help room hours, where he would sometimes demonstrate solving parts of the problem in real time.

Using the Videos

  • Students are encouraged to first attempt the practice problem and then watch the video online to compare with their approach.
  • Students should progress from using the videos to solve the first few practice problems to solving the problems on their homework without assistance

Comments from the Instructor:

  • Making educational videos is nothing new, but making them in screencast format is relatively new.  It is also interesting that I made these videos with the assistance of a cheap camera I purchased on Amazon.  Thus, without any expensive equipment, I made a year's worth of high-quality educational content with nothing more than a Surface Pro tablet, "screencast-o-matic" software (cost: $15) and webcam.
  • The video content and online focus of this project has been important in making this class accessible to students worldwide (e.g., we currently have a student in India).  I believe that this kind of content creation helps to break down barriers to higher education and enables more individuals to pursue knowledge.
  • Give yourself lots of time to make these videos because it is challenging to put together content that is a benefit for someone else.

Sample Videos

  1. Conduction of current in the neuron (also models the neuron as an RC circuit)
  2. Area as a vector
  3. Truth Tables and Digital Logic
  4. Light and optics
  5. Kirchhoff’s Rules