Estimated Time to Complete Lesson
It will take one classroom period to take the students outside to gather their
data. A second period will be necessary to combine all the students' data into
one report of the area.
Teaching StrategyBackground Information
One method scientists use to study an environment more closely is to divide the
area into smaller plots called transects. A scientist can record the location
and number of different animal and plant species that occur in the transect.
Abiotic (nonliving) factors can also be recorded depending on the level of
detail required by the study. If the area is rather homogeneous (the same
throughout) fewer transects need to be analyzed in order to draw some general
conclusions about the area. The more varied the area the more transects need to
be analyzed in order to make accurate general conclusions.
For some species such as certain weeds (like dandelions) it may not be
realistic to count the number of individual weeds in the entire transect since
their number is so large. In such cases a tiny area of the transect can be
selected where the weed is counted and then by the use of multiplication the
scientist can calculate the estimated number of weeds that occur in the
transect (since the weed growth pattern is not identical throughout the
Organize students into groups and provide them with a copy of the
Transect Study activity sheet.
Assign each group a transect (an area of five feet by five feet) to study.
Have students stake out their area using the wooden pegs and rope. Identify
each transect by number.
Using the compass have students determine their N/S, E/W orientation and
record this information on their activity sheet.
Have students `grid' their transect by using the pegs and string. For
example, they may put a string across the transect every foot both in the
north/south direction and in the east/west direction. In this way they can more
accurately locate the geographical features on their transect as they record
them on their activity sheet.
Students should pick out and record the most distinguishing features first.
They should record what they see (naming the species if possible) and the
amount of what they see.
Students should use the colored pencils to indicate grass (green), water
(blue), and soil (brown).
Have students note any effects on their transect due to human activity.
Return to the classroom and combine all the transects together on a poster
board, synthesizing the information into one document describing the area of
Have students comment on the following:
What generalizations can they make about the area?
When all the transects were combined, was the area the same throughout or
different and why?
Did they see any effects of human intervention on their transect? Was it
harmful or beneficial?
How does the area get water? How would the area withstand a drought?
Is the area in danger of dying out? If so, what is the threat and how
soon? Is there anything that can be done to prevent death to the area?
Provides several links, including one to the USDA Plant List, to help identify
Students may be assessed through:
their participation in the outside portion of the activity.
the accuracy and level of detail they provide on their transect study.
the accuracy of the map scale they devised.
the generalizations they make about the entire area once class data is
the quality of their predictions as to how drought and flood rains
might affect the area.
Research and write a report on some of the species they found. Let
students choose which of the plants and animals they found to research. Have
them look for such information as the animals' natural distribution, life
cycle, and predator-prey relationships in the food chain.
Design a bulletin board that displays the transect study. Make
sure to include some of the information that the students found in their
research (from Procedure Step #1 above).
Return to students' transect every two months. This way, students can
see how the population changes depending upon certain variables, like time of
day, temperature, or season. Students who keep a log of the changes can return
to their data and look for patterns and make predictions about what they might
see at the same spot in the future.