I call students to the gathering area and we review that we looked at how a bi-ped (two-footed) creature moved. We looked at a human leg skeleton and we are going to draw that today.
I tell them that once we have drawn that bone, we will compare the movement of a quadra-ped (four-footed animal).
Using the information learned in the previous lesson about making scientific drawings, students draw a human leg skeleton from a poster I have for them.
I give students a rectangle of white paper. This is about one fourth of a sheet of paper. This offers students parameters for size and scale. These papers can be pasted into students' interactive science notebooks after drawings are complete.
We watch a movie of a lion walking. One of the best free videos I have found is on vimeo: Lion Walking Video.
I ask students how this lion is able to move in such a way. Students often start to say things like, because she has four legs. I ask them to be more explicit in their descriptions. I ask them to observe what is happening to the lion’s body as she performs these movements.
We watch the video a couple of times, looking at different parts of the animal: hips, ankles, feet, and knees.
After we have done this, we discuss how different body parts are used for different kinds of movement. I show students a picture of a lion skeleton. We discuss how the skeleton is designed to facilitate the manner in which a lion moves.
Students move back to their work-space and begin to look at a poster of a lion skeleton. Students work to make a scientific drawing of the lion’s skeleton.
When students are done drawing they begin to make observations of the differences and similarities between the human leg and a lion’s leg. They fill in two parts of a three-part venn diagram. The third part is filled out during the next lesson, after examining a bird’s movement and skeleton.
I remind students that we observed the movement of a creature that walks on four legs. We discussed the skeleton structure that we thought contributed to efficiency and survival for a four-legged creature.
We looked at the structure of a leg of a four-legged creature and discussed its characteristics. We also look at our venn diagram and compare and contrast the human leg and lion leg.
Looking ahead: we will look at creatures that fly and observe the similarities and differences in structure of these animals.
Assessment
I assess student understanding using the human leg drawing and the three-way venn diagram information.