NCDPI – AIG Instructional Resource: Background Information
Resource Title: Simple Machines to the Rescue: Save Mrs. Frisby’s Home
Subject Area/Grade Level (s): Science/7
Time Frame: 5 class meetings (60 min each) Modified version: 2 class meetings
Common Core/Essential Standard Addressed:
ES 7.P.2.4 Explain how simple machines such as inclined planes, pulleys, levers, and wheel and axles are used to create mechanical advantage
and increase efficiency.
Additional Standards Addressed:
CC ELA R.7.3 Analyze how particular elements of a story or drama interact (e.g., how setting shapes the characters or plot).
CC ELA SL.7.1 Engage effectively in a range of collaborative discussions (one-on-one, in groups, and teacher-led) with diverse partners on grade 7
topics, texts, and issues, building on others’ ideas and expressing their own clearly.
CC Math 7.RP.2 Recognize and represent proportional relationships between quantities.
Brief Description of Lesson/Task/Activity: Within the physical science strand of 7th grade science, students focus on forms of energy, energy
transfer, and transformation and conservation in mechanical systems—in other words, potential and kinetic energy, work, and mechanical
advantage and efficiency in simple machines. In this task, students working in groups design a simple machine or simple machine system that
would be able to lift and relocate a 13 kg cinder block after reading an excerpt from Mrs. Frisby and the Rats of NIMH by Robert O'Brien, a novel
about genetically engineered rats who assist a mouse by moving her home out of danger in a farmer’s field. The interdisciplinary and inquiry
based nature of this activity allows students to build meaningful connections while promoting creativity and 21st Century Skills.
Type of Differentiation for AIGs (include all that apply):
Adaptations for AIGs:
Content
x Process
x Enrichment
Extension
Acceleration
x Product
PUBLIC SCHOOLS OF NORTH CAROLINA State Board of Education | Department of Public Instruction
AIG ~ IRP Academically and/or Intellectually Gifted Instructional Resources Project
Explanation of How Resource is Appropriate for AIGs: AIG students in the middle grades easily grasp the types and benefits of each of the six
major simple machines. The evaluation of simple machines in terms of their mechanical advantage and efficiency also is easily accomplished by
students with advanced math reasoning. The combination of the fictional reading with the task of actually constructing a simple machine with
the greatest MA to complete a task is a more appropriate assignment for AIG students. Working collaboratively with other students to
accomplish a task will also help develop interpersonal skills.
Needed Resources/Materials
 Copies of the novel or copies of the excerpt from Mrs. Frisby and the Rats of NIMH by Robert O'Brien
- Chapter 5 “Five Days”
- Chapter 8 “Go to the Rats”
 Copy of the animated G-rated movie The Secret of NIMH based on the O’Brien novel (optional)
 Pulleys, wheel and axles, levers, inclined planes, and other building materials for student use
 Masses equal to a 13 kg cinder block or an actual 13 kg 8x8x16 cinder block
 Spring scales or other force meters
 Calculators
 Rubric for scoring the group machine model
Sources:
 Mrs. Frisby and the Rats of NIMH by Robert O'Brien
 The Secret of NIMH movie produced by United Artists
TEACHER NOTES: Some prerequisite knowledge/skills are required. Students should have demonstrated proficiency at identifying simple
machines and calculating their mechanical advantage and efficiency. If the school lacks the equipment for students to physically construct their
machine models, alter the timing and assignment to allow students to design the machine models as a poster to be displayed.
In addition, teachers can make connections to the following Essential Standard through additional discussions/activities not included in this
lesson: ES Science 8.L.2 Understand how biotechnology is used to affect living organisms.
NCDPI AIG Curriculum Resource Outline
STAGE ONE: ENGAGE
DAY ONE:
Provide copies of the novel excerpts to students and have them read them aloud. Discuss the problem faced by the main character, Mrs. Frisby,
(the need to relocate her home within 5 days without disturbing her sick son) and the rising action (her attempts to locate others who can help her).
PUBLIC SCHOOLS OF NORTH CAROLINA State Board of Education | Department of Public Instruction
AIG ~ IRP Academically and/or Intellectually Gifted Instructional Resources Project
Explain that students will be completing a RAFT activity based on the novel. Students will be assuming the Role of the genetically engineered rats
who have agreed to help Mrs. Frisby. The Audience will be Mrs. Frisby and Nicodemus (the teacher and other students) who will be evaluating
the final product. The Format will be the constructed (or poster) model of the machine system that will address the Topic---the ability to
successfully lift and relocate Mrs. Frisby’s home.
Review simple and compound machines, as well as the formulae for mechanical advantage and efficiency as necessary.
STAGE TWO: ELABORATE
Arrange students in groups of three to four students if they are not already in defined working lab groups. Remind students of collaboration
procedures and expectations.
Provide students with the rubric for scoring the final product. Key elements on the rubric should include:
 The use of at least three simple machines that must work together to accomplish the task
 A written explanation as to how the machine(s) work
 A written explanation of the concept of MA (to include IMA and AMA for working model only)
 The accurate calculation of the MA for each part of the model (to include differences between IMA and AMA for working model only)
 The successful movement of the 13 kg mass (working model only)
Provide students with time to begin planning their machine.
As the teacher circulates, ask leading questions as necessary, such as;
 What simple machine could lift the home? How can you maximize the ease of its use or MA?
 After it is removed from the ground, what simple machine could move the home from that location to its new location? How can you
maximize the ease of its use or MA?
 Once you have the home at its new location, what simple machine could lower the home into its new location? How can you maximize
the ease of its use or MA?
DAYS TWO, THREE, and FOUR:
Review safety rules and procedures with students. Provide any necessary eye/hand protection. Review the scoring rubric.
Students should work collaboratively in their groups to construct a working model. Encourage students to document their trial and error process
and learn from their mistakes. As necessary, continue to ask the leading questions from Day One.
PUBLIC SCHOOLS OF NORTH CAROLINA State Board of Education | Department of Public Instruction
AIG ~ IRP Academically and/or Intellectually Gifted Instructional Resources Project
STAGE THREE: EVALUATE
DAY FIVE:
Student groups will demonstrate their models for the teacher and their classmates. Student groups should be evaluated based on the rubric
provided earlier. If time remains, consider showing the movie clip demonstrating how the rats of NIHM chose to move Mrs. Frisby’s home and
compare/contrast their method to the methods designed by the class.
TEACHER NOTES: Teachers may also want to consider adding an individual participation/ group collaboration segment to the final product
rubric to allow students to more effectively reflect on their individual behaviors and group dynamics to foster further development of these
social skills.
PUBLIC SCHOOLS OF NORTH CAROLINA State Board of Education | Department of Public Instruction
AIG ~ IRP Academically and/or Intellectually Gifted Instructional Resources Project