Quicksand Questions: Short In-class Activity

Activity and Starting Point page by L.A. Guertin ( This site may be offline. ) , Penn State Univ. Delaware County, Earth Science.
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This material was originally created for Starting Point:Introductory Geology
and is replicated here as part of the SERC Pedagogic Service.

Initial Publication Date: September 7, 2006


Students are prompted with questions during a lecture on quicksand. Student answers can be collected with classroom response systems. The responses (both individual and the class as a whole) are recorded on the instructor's computer. Alternatively, students can be asked to respond using a think-pair-share activity. In either case, an instructor can review the answers with the class and immediately address any points of misunderstanding or content areas that need clarification.

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Learning Goals

  • To reinforce lecture material, to make sure that students can apply what they have just learned.
  • To allow students to provide their own individual response to a question, to choose an answer NOT based on peer responses.
  • For the instructor to assess student comprehension of material at an individual and group level.

Context for Use

Ideally, students should be asked questions during the lecture period, right after the quicksand topic is introduced. The questions can be shown in a Microsoft PowerPoint slide, on an overhead sheet, or written on the board in the front of the classroom. Each student should have a handheld course response unit (either networked or IR) in hand to select their answer or can discuss their answer with another student if the question is part of a think-pair-share activity. Students may need as little as 15 seconds to respond using a classroom response system; the think-pair-share activity would take a bit longer. An instructor may want to spend another 30 seconds to 1 minute for further discussion and clarification of responses (if necessary).

Description and Teaching Materials

Here are two sample questions about quicksand to ask students during lecture with classroom response systems.

Question: True or False: A person can disappear entirely in quicksand.

Answer: False. Quicksand is twice as dense as water, so humans will only sink chest deep. It is virtually impossible to disappear in quicksand.

Instructors may find that most students will respond with "true" as an answer. Hollywood horror films are typically the reason students respond with a "true" answer, since actors and actresses are shown sinking entirely in quicksand. This point can then lead into a discussion of how science is portrayed in Hollywood and other forms of media.

Question: Multiple Choice: Which of the following quicksand facts is FALSE?
(a) the finer the sand particles, the tighter and more vice-like the grip
(b) if you step in quicksand, pulling your foot straight up is the easiest way to escape quicksand
(c) earthquakes can generate quicksand
(d) quicksand can be found anywhere sand and water exist
(e) quicksand can have enough pressure to cause loss of circulation in limbs and may even crush bones

Answer:(b) pulling your foot straight up will only compact the sand. If you get a foot caught in quicksand, the best action is to slowly wiggle the foot loose.

Instructors may see a wide range of student responses, depending on whether the instructor has directly addressed these statements or if students must apply what they have learned to these situations.

Teaching Notes and Tips

  • An instructor may want to ask one or both of these questions before lecturing on quicksand to see what the prior knowledge is of the class. The responses can help direct the lecture.
  • An instructor may wish to show clips from or the entire video of "Danger! Quicksand!" from National Geographic to supplement the course material.


For both questions, assessment of student responses is instantaneous through the classroom response system software. Instructors can view a graph that tallies the answers and display that graph to the class. The results shown in the graph can be a continued point for discussion and may show the instructor that some clarification of the subject material is necessary.

In addition to the group response, classroom response system software creates a record of each individual student's answer. Over time, the record of individual responses will allow an instructor to see if a student is struggling with the course material overall through the semester.

Assessment of student responses will take a few minutes if the activity is done as a think-pair-share.

References and Resources