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Which One?

Which One?

An observation activity to prepare for an Exploratorium field trip

What Is Appropriate for My Students?

Grades K–5
Your students will be surprised that they can find their own pencils in a pile of pencils that initially all look the same. The memory of successfully making careful observations to play this game will help students in later investigations. With this age group, there is no need to have students take notes on their observations—they can be discussed aloud.

Grades 6–8
Your students will be able to appreciate that the more they notice about their pencils, the more successful they will be in this activity. The follow-up discussion will help them recognize the relevance of detailed observations to scientific investigations. They should be able to be deliberate about making careful observations at Exploratorium exhibits.

Grades 9–12
Making careful observations is a skill that is practiced and refined through adulthood. The last steps of this activity, finding a partner’s pencil, will be most meaningful to your students as they begin to think about scientific investigations. High school students should be able to apply these concepts to observations at the Exploratorium as well as to observations they make every day in and out of school.

What You Need

  • 1 pencil for each student (or other common objects such as pinecones, rocks, or erasers)
  • notebooks and writing instruments (optional)

What to Do

This activity works well with students sitting in a circle with an open space in the middle.

  1. Pass out one pencil to each student (or have them use their own). Other objects may be used for this activity as well. Objects that work best are ones that initially all look very similar but have slight distinguishing features. For example, thirty used No. 2 yellow pencils have a uniform look but have slight differences in size and wear.

  2. Ask students to examine their pencils (or other objects) using any senses they like and think of two characteristics that might make their object unique. Optional: You may choose to ask students to record their observations in a notebook through writing or drawing.

  3. Have students put all of their pencils into a pile in the center of the group. While students close their eyes, mix up the pencils.

  4. Ask for a volunteer to try to find his or her own pencil. This may prove to be challenging for some groups, and easy for others.

  5. If the student finds the pencil, ask him or her to share with the group what the distinguishing characteristics are. If the student does not find the pencil, ask why this is a challenging task.

  6. Ask for more volunteers as time allows.

  7. If students were challenged by this activity, allow them to repeat the process and try again. Students will probably make more careful observations the second time.

  8. If students were successful, repeat steps 1–3. This time, have students make as many observations as they think is appropriate.

  9. Ask students to choose a partner and share their pencil observations with their partner.

  10. Ask for a volunteer to find his or her partner’s pencil. Is this task more challenging? Why? What could be done to make it easier?

What to Talk About

  • What was surprising about this activity?
  • What did you do differently the second time? Why?
  • Which senses did you use to make observations? Could other senses have been used as well?
  • If finding your pencil were a scientific investigation, would another scientist be able to repeat it based on your observations? Why would this matter?

So What?

Scientists always start by making careful observations. Examining things closely sometimes leads people to wonder about them. This is the beginning of scientific investigations! Also, scientists need to be able to repeat the experiments of other scientists exactly. This means making good observations and recording them very carefully. On your trip to the Exploratorium, be sure to take a very close look at the exhibits. Ask yourself, “What else do I notice?”

California Science Standards

The California Science Content Standards include observation skills as building blocks to scientific investigation for grades K–12.