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Lesson 10
Using Math Connections to Collect and Document Specimens

Learning Objectives

Students will:

  • Measure length and width of leaf samples to the nearest millimeter and the circumference of trees;
  • Calculate the diameter of the same trees;
  • Calculate the height of the trees using ratio and proportion.


This lesson correlates to the national McREL standards located online at


Standard 2: Understands and applies basic and advanced properties of the concepts of numbers

Standard 3: Uses basic and advanced procedures while performing the processes of computation

Standard 4: Understands and applies basic and advanced properties of the concepts of measurement

Standard 8: Understands and applies basic and advanced properties of functions and algebra

Language Arts

Standard 1: Uses the general skills and strategies of the writing process

Standard 4: Gathers and uses information for research purposes.


NOTE: In order to access and print Student Activity Sheets, you will need Adobe Acrobat. If you do not already have this tool, you may download Adobe Acrobat free of charge at the Adobe Web site.

  • Outdoor classroom or wooded area
  • Large measuring tools (meter sticks, measuring tapes, etc.)
  • Journals (can be made of construction paper and copy paper in advance by the teacher or by students as part of the activity)
  • Double-sided tape
  • Lesson 10 Student Activity Sheet

Time Needed

Two 90-minute or three 45-minute class periods.

Teaching Strategy

NOTE: For this lesson it is assumed that students comprehend the use of ratio and proportion.

  1. Create interest by having students imagine that they have been commissioned by President Jefferson to document the vegetation in their area. Remind them it is critical that their data be accurate and specific so that the information can be added to current books and research materials.

  2. Direct students to the Inside the Corps section of the Lewis and Clark Web site. There, choose “Circa 1803” and read the section entitled “The Idea of the West.” Based on the common misconceptions of the time, facilitate a discussion about the importance of collecting specimens carefully and compiling accurate information in the journals and reports.

  3. Distribute copies of the Lesson 10 Student Activity Sheet and review strategies for setting up ratios and solving proportions. Do 2-3 sample problems as part of this review.

  4. Distribute journals or materials for constructing journals. Provide students 3-5 minutes to put journals together if they are constructing them.

  5. Tell students what to collect on the outdoor specimen collection activity including

    • l the number of samples that need to be collected (perhaps suggest a scale that would make 3 leaf specimens collected and documented properly worth a C grade, 4 a B grade, and 5 an A grade)

    • l data that must be collected from each sample (i.e. length and width of each leaf, measurement of the circumference of the trunk where leaf came from)

    • l shadow data needed to determine the height of each tree.

  6. Have students collect leaf samples and take/record required tree measurements.

  7. Return to the classroom and mount each leaf sample individually on a page of their journal using double-sided tape.

  8. Next, students should write a paragraph for each leaf specimen including

    • l a brief description of each tree, including specific details about the general appearance of the tree

    • l the measurement of the leaf samples (length and width measured to the nearest millimeter)

    • l the measurement of the circumference of each tree trunk

    • l calculation of the diameter of each tree

    • l the measurement of height of each tree based on calculations made from applying information about ratio and proportion. Students should show all of their math computation on the pages of the journal.

  9. Compile data in the form of a written report that could be sent to President Jefferson. Write a least one complete paragraph about each specimen collected and the data based on the sample.

  10. Have students take turns sharing reports with their classmates in small groups OR have students use a peer evaluation form to provide feedback to one another by working in pairs to share completed reports.

  11. Post reports in a prominent place in the classroom for others to see and refer to.

Online Resources

    American Field Guide


    Journey Into Amazonia

    Nature: The Lost World

    Secret Garden

    How Evolution Works

Assessment Recommendations

  • Create a scoring guide to be used to assess the content of each student journal.
  • Give a participation grade for sharing journal in small groups.
  • Create a student evaluation form and have students use it to practice giving one another feedback on their projects.


Use this lesson as part of a larger unit connecting mathematics and nature. For example, extend this into a lesson on the patterns discovered by Leonardo Fibonacci. Useful Resources can be found at this University of Surrey Web page.