Detectives - Shape and Size
Primary Lesson Plan (2nd - 5th)
Werner (1999) Girdwood, Alaska
||The recent discovery of Alaskan North Slope
dinosaur tracks provides further evidence that
dinosaurs not only lived, but also thrived in
the polar regions. In this exercise students will
become detectives who are searching for clues
from tracks. The following are some suggestions
for fun hands-on investigations.
||After completing this lesson, students will
be able to:
- Classify the tracks of many different animals
according to size, stance, and shape.
- Understand that a series of tracks is a
clue to the maker's size, stance, speed, and
- Understand the role and process of a research
- Variety of real-sized cat, dog, bird, and
dinosaur tracks (see page attached)
- Track worksheet (see page attached)
- Buckets or pans of mud, sand, and dry dirt
- Chalk and board or paper and marker
- Fork, knife, and spoon hidden in a paper
- Large inkpad and paper
- Print and Assemble Dinosaur
and Modern Animal Tracks
||SHAPE AND SIZE VARIATION
||Begin the lesson with a question/answer period.
Start this by drawing a circle on the board and
ask students what needs to be added to create
a dinosaur. They will say the obvious- eyes, ears,
nose, and mouth. Encourage them to be specific.
Are the eyes on the front or side of the head?
Do the ears stick out like humans or are they
simply holes like reptiles? Continue with a discussion
of anatomy and dinosaur ADAPTATIONS. Introduce
the following terminology: bipeds, quadrupeds,
carnivores, herbivores, and digits. Listed below
are a few sample lead-in questions.
Conclude the brainstorm of dinosaur ADAPTATIONS
and then explain to the students that they will
now learn how scientists figured out some of these
- Do they all eat the same types of food?
If a group of dinosaurs were going to order
a pizza, would some order meat and some order
veggie pizzas? What kind of teeth would be
better for a meat-ripping carnivore compared
to a plant-grinding herbivore?
- How many digits (toes and fingers) do you
have? Do all dinosaurs have the same number
of digits? Different dinosaurs adapted with
different numbers of digits. Was it because
they used their toes and fingers for different
purposes? Dinosaurs with four digits per limb
used them for stability and balance on the
ground. Dinosaurs with three-digit limbs used
them for holding and grasping prey.
|Using the dinosaur and modern animal track images,
compare different animal tracks. In groups of
3 or 4, have them divide tracks into different
categories based on the similarities that they
observe. Each group may present their findings
to the other groups. Ask them for the words that
describe the similarities; ex: size, shape, number
of toes, or claws.
Next, instruct them to look only at dinosaur tracks
while you get the paper bag with the fork, knife,
and spoon. The fork and knife are symbolic of
meat-eating carnivores while the spoon is representative
of the plant-eating herbivores. Choose three volunteers
to come pull a hint from the bag. Compare the
shapes of the fork, knife, and spoon to the dinosaur
tracks. Ask students to look at the tracks again.
This time they should notice that some are pointed
and sharp like a fork and knife. Others are blunt
and rounded like a spoon. This is one method scientists
use to classify carnivores and herbivores.
**Optional Activity: Students press their feet
or hands into large inkpads to create tracks on
a piece of paper. Students should compare their
prints to other classmates'. A hide and seek game
can be played. Scientists are the seekers and
dinosaurs are the hiders. The dinosaur team will
leave tracks leading in the directions of their
hiding spot. They can hide the tracks to make
the hunt more challenging. This is similar to
the way that dinosaur tracks could lead to hiding
places or water sources.
||BE A RESEARCH TEAM:
A good scientist must know WHERE to look for clues.
Ask students to remember the last time they made
a track (or got in trouble for making a track).
Many will respond that they have made mud tracks
or dirt tracks. At this point, introduce the buckets/pans
of mud, sand, and dry dirt. Ask students to hypothesize
which medium will best preserve their track. Allow
students to work in smaller groups to explore
the effects of their thumbprints in the different
mediums. Explain to students that the sand, dirt,
and mud all turn to rock after lots of time and
pressure. Allow them to decide what kind of rocks
they may find dinosaur tracks in - sandstone,
|Review findings with students. Ask them what
clues scientists use to learn about dinosaurs.
If there is time, let them create their own imaginary
dinosaur print. They can investigate their creation
as well as each others' dinosaur tracks for size,
speed, and other elements of lifestyle.
dinosaurs - One group of extinct
reptiles (orders Saurischia and Ornithischia)
that lived during the Mesozoic
anatomy - The structure or
parts of an animal like the skeletal system.
carnivore - A meat eating
herbivore - A plant eating
digits - A finger or toe.