Name: John Doe and Jane Smith
Date: May 12, 2000
Course: Seventh grade integrated science
I. Goal(s):
· To develop the concept of simple machines and mechanical advantage
II. Objective(s): The student will
· Distinguish between the three classes of levers.
· Calculate the mechanical advantage of any lever.
· List examples of the three classes of levers.
Alabama Course of Study Objectives – Integrated Science: 7th Grade – Content Standards 31, 32, 33
National Science Education Standards – Grades 5-8 Content Standard B
III. Materials and Technology:
Demonstration items (hammer, wheel barrow, fishing rod), lego dacta sets and rulers per pair of
students, student handouts
IV. Safety Precautions: Students will be briefed on proper handling of the lego dacta sets.
Inclusion: Student in wheelchair will have access to materials at lowered lab table.
V. Lesson Procedures: [Not all phases of the Learning Cycle are often present in one 50-min. lesson]
A. Opening (15 minutes) – ENGAGE PHASE
Discuss the three classes of levers with the students and what distinguishes them from each other. Focus on the question: How do levers make work easier? [See TEACHER NOTES attached].
B. Activity (15 minutes) – EXPLORE PHASE
Student pairs use Lego Dacta sets to build their conceptions of first, second, and third class levers. Selected pairs of students share their example constructions with the class to determine if they meet lever requirements.
C. Directed Teaching (15 minutes) – EXPLAIN PHASE
Teacher comes back to point of “making work easier” by teaching the concept of
mechanical advantage on the board. Students are asked to try some example problems which are checked for understanding. Students are then given a handout on individual lever drawings in order to determine the class of lever, its mechanical advantage through measurement and calculation, and how it makes work easier. [See STUDENT HANDOUT attached.]
D. Closing (10 minutes) – ELABORATION PHASE
Teacher demonstrates real-life uses of the three classes of levers showing a hammer
removing nails from wood (1st class), a wheel barrow lifting a load (2nd class), and a
fishing rod reeling in a fish (3rd class). Students are again asked why each of these are
examples of each type of lever.
VI. Additional:
Have students work through additional problems on lever class and mechanical advantage given on the overhead.
VII. Evaluation:
Student handouts will be collected and checked for accuracy (formative assessment). A performance quiz on levers will be given in two days where students will identify the class of a given lego setup and calculate the mechanical advantage after measurement; later identifying if the setup makes work easier.
VIII. Assignment:
Identify one new example of each class of lever at home, listing its name, class, estimated mechanical
advantage, and if it makes work easier or not.