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A New Twist on Mystery Boxes: A Summary
Article by Gerald Rau in The Science Teacher (NSTA), November, 2009
Permission to use, with downloadable pages, courtesy of Gerald Rau (
PDF Copy of this page

This lesson satisfies most of the basic understandings about the nature of science that are targeted by the NGSS (Next Generation Science Standards, 2013).

[It] was developed over the course of several years as an initial activity to refute the common misconception that science follows a single, universal method. The activity facilitates an understanding of the nature of scientific inquiry and has been successfully implemented, with minor changes, in classes from middle school through college. Although developed as a bioligy exercise, with different objects, the same activity could easily be modified for use in Earth, life, or physical science classes.

[The] activity is used to help students learn about observation, interpretation, and argumentation. Students are led through several stages of observation and inference about an unknown object, during which they learn the value of representations and collaboration. They are then asked to construct an argument about the identity of the object and the process of its formation. Instructions for conducting the activity and a rubric for scoring the assignment are also provided.[Y]ou will need to obtain one object per student. Choose objects students will not recognize easily, but that have identifiable characteristics. All objects should be produced by a once-living organism and modified in some way, either by natural or human activity.

Some objects that have worked well include:
seashells (clams, snails) or coral worn by the surf
dried sponges or seaweed
galls or growths broken from a plant
dried or worn corn cob or palm fiber
dried luffa or the rib of a cactus
pine cone eaten by a squirrel or run over by cars
the seed of a Norfolk Island pine or mango
the dried core of lettuce or skin of an avocado
fossil or piece of bone
More objects to consider:
piece of driftwood (ocean-weathered branch or small board)
coprolite (fossil feces)
broken peanut shell, coconut, or sliced cucumber
spines of a pencil urchin, squid pen, or cuttlefish bone
dried sea star, urchin test, limpet shells, or chiton plates
garden mulch (chopped or shredded bark)
crushed leaf, sliced orange, lemon, squash, or apple
cotton shirt, wool shirt, or book
wood sculpture of bird, fish, etc.

First observations and inferences are done by feeling and lifting the object (hidden from view in a box). The author eventually (step 7) allows visual observations. [However, it would be interesting to omit step 7. There are many phenomena that observers never really get to examine visually or directly close up (like the center of the Earth, atomic structure, composition of stars, etc.). As a result, scientists never really know exactly the real answer to their questions about nature; they can only try to get as close as possible to that knowledge, close enough for all practical purposes. Ed.]

In the discussion, students are asked to argue for the identity of the object and how it came to be in its current state (was it broken, worn, crushed, or eaten?), supporting their argument with the evidence. In the reflection, they are asked to relate the lab activity to the way a scientific investigation is conducted, and to compare the order of obtaining information in the lab to the order of the final presentation.

[Students are assessed primarily on] how well they present their evidence and argue their conclusion based on the evidence.

[The author uses] this activity within the first week of class to set the tone for the rest of the course. It introduces several important topics from the nature of science (a major theme in science education) and helps prepare students for inquiry by teaching them to distinguish evidence from inference and how to construct scientific arguments. The gradual accumulation of evidence over the course of the activity helps students understand why scientific knowledge changes over time. It also stimulates their curiosity: they find themselves asking questions about their objects that will be answered later in the year. Not bad for one class!


The author has kindly made available several items (in pdf) to facilitate the use of his approach. With his kind permission, we provide those four items for free download (for class uses only) here. Just click on desired item:
Reprint of the article
Steps for doing the activity (for teacher)
Handout for students
Rubric for grading student reports

Editor Note:
If possible, introduce specific aspects of scientific argumentation, as explained and used in the several articles of NSTA The Science Teacher (TST) for the Summer of 2013. One of them, Making and Defending Scientific Arguments by Douglas Llewellyn (pp. 34-38) does this using a mystery box, for example. When students claim a particular configuration in the box, they are expected to state the evidence for that claim, then justify or explain why that evidence points to the stated claim. While practicing this in small groups and then in the entire class, other students are expected to provide rebuttals and other claims based on counter-evidence. The Mystery Boxes lesson is a natural place to introduce and encourage these critical exchanges based on evidence. The article also suggests a number of other topics that would be suitable for argumentation.

An interesting structure for scaffolding constructive and objective argumentation (using MEL diagrams) is presented in the same TST issue. See What's the Alternative? by Doug Lombardi et al (pp. 50-55).