A Video Lab is a rich problem solving exercise driven by a short and engaging video that demonstrates a physics concept and prompts student questions. While textbooks TELL students a problem, video labs SHOW students a problem--a powerful distinction that benefits student learning. At this website you'll find links to videos to use for video labs, and downloadable student handouts/lesson plans you'll can use to capitalize on the benefits of video in the classroom.
What's Wrong with Word Problems?
Many textbooks attempt to provide students with "real world" physics problems to solve, such as the one reprinted below. If a teacher's intent is simply to drill students on plugging in variables, then this problem is fine. But if a teacher intends to develop students' real world problem solving skills, style of word problem fails on three counts:
Failure 1. It is not a "real world" problem.
Surely every student has sure dropped a pebble (or some other object) down a well (or from some other height) before in their lives. And they can create a mental picture of themselves within the problem, dropping the pebble down the well. But when was the last time anyone ever encountered an actual problem in real life that immediately provided all the information require to solve the problem, identified exactly what quantity must be solved for in order to answer the question, and clearly stated which mathematical relationships to use to calculate the answer? Content does not make a problem a "real world" problem, context does.
Failure 2. It does not foster true problem solving skill.
Determining what mathematical relationships will help you answer a question, determining which variables would be required to utilize those mathematical relationships, and determining what question to pose in the first place are all very important part of true problem solving. This textbook problem gives away all of this information, depriving the student of an opportunity to exercise and develop these valuable problem solving skills.
Failure 3. It's boring.
There is nothing in this problem that engages the student in any meaningful way. It does nothing to foster curiosity or interest in the solution. The typical student will have a vested interest in completing the problem correctly rather than discovering the answer.
In short, this style of text-based problem TELLS a student a problem.
Video as an Alternative
While a text-based problem TELLS a student a problem, a video has the power to SHOW a student a problem--a huge advantage. Replacing a word problem with a video can engage the student with a problem, getting him/her curious and interested in determining the answer. Furthermore, a video-driven problem leaves variable measurement or estimation up to the student, leading to a much richer problem solving experience. Finally, a problem solving sequence of becoming curious about a situation, identifying what quantities might be able to help satisfy one's curiosity, and then determining those quantities and solving for an answer is an authentic "real world" problem solving sequence.Â
Here's how video replaces and improves the "pebble down a well" problem. First, show the students this video:
Second, let the students' curiosity flow for a moment. Ask them what questions this video brings to mind. For this video, they're likely to come up with a pair of physics-related questions:
1. Is the hole really 1500 feet deep as the title of the video claims?
2. How fast is the rock going when it hits the bottom?
Note that the first question covers the exact same physics content as the textbook's "pebble down the well" problem. The second question is only slightly different (still a 1D constant acceleration problem) and just as valuable/interesting.
Third, let the students get to work. As the students begin problem solving, they'll realize that the need to know the time that the rock was falling. Then they'll realize that they can figure out this time, either with a stopwatch or by looking at the changing timestamp in the corner of the video. Then they'll realize that they need to make an assumption about the initial velocity of the rock, and they'll need to make a good estimate. These realizations are powerful problem solving moments that are completely absent in the textbook version of the question. Answering a question this way develops strong and rich problem solving skills.
What about air resistance? What about the speed of sound causing a delay in hearing the impact of the rock? After the students have come up with their answers, ask them to think about if their answer is likely to be greater than or less than the true depth of the hole, and ask them to explain why. Reflecting on an answer's accuracy/realism is an important step in real life problem solving. Again, this step is non-existent in the textbook version of the question--the student "check for accuracy" by comparing his/her answer to the one in the back of the book.
What Does this Look Like in the Classroom?
Students can work on a video lab individually or in small groups using a laptop, iPad, or other web-connected, video-capable device. The student handouts provided on this website can be given to each student or group of students to structure their video lab.
Video labs can also be conducted by the class as a whole, with the video being projected to the entire class and the instructor (or a student) coordinating ideas and data on the board. In these situations, the student handouts provided on this website will useful guide to the instructor as he/she facilitates the video lab.
A Great Resource
Check out math teacher Dan Meyer's blog and his "three act tasks." Though math focused, I find them inspirational when thinking of new video labs to create, and much of my work with video labs has been inspired by his work.