Hands-on Activity The Mummified Troll:
Devising a Protection Plan

Quick Look

Grade Level: 7 (6-8)

Time Required: 30 minutes

Expendable Cost/Group: US $0.00

Group Size: 2

Activity Dependency:

Subject Areas: Physics, Science and Technology

NGSS Performance Expectations:

NGSS Three Dimensional Triangle

Photo shows a bronzed-looking, standing troll doll with big hair.
Our treasured Mummified Troll!
Copyright © 2008 Terry Carter, Vanderbilt University


Students are introduced to the parameters of an engineering challenge in which their principal has asked them to devise an invisible security system to cost-effectively protect a treasured mummified troll, while still allowing for visitor viewing during the day. Students generate ideas for solving the grand challenge, first independently, then in small groups, and finally, compiled as a class.
This engineering curriculum aligns to Next Generation Science Standards (NGSS).

Engineering Connection

Through this activity, students are presented with a need in society and asked to find a solution—a scenario otherwise known as the engineering design process. Just like engineers, students begin by identifying the need, and then defining the challenges that must be considered in the design. Before the next phase, research, students must identify the information they need to acquire through their research. Engineers of all types constantly follow the engineering design process, with the first and most crucial steps being identifying the need in society. Like engineers, students must learn to apply their peripheral knowledge to solve the identified need.

Learning Objectives

After this activity, students should be able to:

  • Apply their background knowledge to begin solving the challenge.
  • Identify types of security systems that may apply.

This activity also meets the following Tennessee Foundations of Technology educational technology content standards: 3.0, 5.0, 6.0, 7.0 and 8.0.

This activity also meets the following National Science Education Standards (NSES) teaching standards: A, B, C, D, E, F; see https://www.nap.edu/topic/

Educational Standards

Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards.

All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standards Network (ASN), a project of D2L (www.achievementstandards.org).

In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc.

NGSS Performance Expectation

MS-ETS1-1. Define the criteria and constraints of a design problem with sufficient precision to ensure a successful solution, taking into account relevant scientific principles and potential impacts on people and the natural environment that may limit possible solutions. (Grades 6 - 8)

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This activity focuses on the following Three Dimensional Learning aspects of NGSS:
Science & Engineering Practices Disciplinary Core Ideas Crosscutting Concepts
Define a design problem that can be solved through the development of an object, tool, process or system and includes multiple criteria and constraints, including scientific knowledge that may limit possible solutions.

Alignment agreement:

The more precisely a design task's criteria and constraints can be defined, the more likely it is that the designed solution will be successful. Specification of constraints includes consideration of scientific principles and other relevant knowledge that is likely to limit possible solutions.

Alignment agreement:

All human activity draws on natural resources and has both short and long-term consequences, positive as well as negative, for the health of people and the natural environment.

Alignment agreement:

The uses of technologies and any limitations on their use are driven by individual or societal needs, desires, and values; by the findings of scientific research; and by differences in such factors as climate, natural resources, and economic conditions.

Alignment agreement:

  • Students will develop an understanding of the relationships among technologies and the connections between technology and other fields of study. (Grades K - 12) More Details

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Materials List

The Challenge of Protecting the Mummified Troll Worksheet

Worksheets and Attachments

Visit [www.teachengineering.org/activities/view/van_troll_lesson01_activity1] to print or download.

Pre-Req Knowledge

A basic understanding of security systems.


Today let's begin to consider and record our initial thoughts in response to the engineering challenge. First, we must consider what background knowledge we already possess that can be applied to solving the challenge. Then, we must consider exactly what we need to learn in order to devise a protection plan for the mummified troll. I am passing out a worksheet that I would like each of you to complete, first recording your own thoughts. After recording your own initial thoughts, we will work in small groups to expand our ideas.

So let's jump start our thoughts. As I ask you a few questions, jot down any thoughts that enter your mind. How do security systems work? Do you know of any invisible security systems? What do you know about laser-based security systems? If you are not sure what a laser-based system is, let's think about light properties. What do you know about light's properties? What happens when light hits an object? How could we use what we know about light properties to keep our troll safe? (Scale leading questions to the level of the class.)



This activity introduces students to the material they be learning in an exciting, unique manner. Students first begin generating ideas on the challenge question and then contribute to class discussion in an engaging manner.

Begin with students working alone to record their personal thoughts and ideas by answering the generate ideas question on the worksheet. After an adequate amount of time, generate a class list on the board of concepts that must be considered to solve the challenge question. Next, ask students to create a list of knowledge areas and categorize the concepts they have listed into these knowledge areas. Work with students until they arrive at the following three comparative knowledge areas: basic properties of light, laser types and applications, and the construction of a laser security system.

Before the Activity

With the Students

  1. Describe the challenge to the students (at top of worksheet).
  2. Hand out the worksheet and ask students to take notes on it individually for a few minutes.
  3. Divide the class into small groups of two or three students each, and have students share their thoughts with each other.
  4. Ask students from each group to volunteer their thoughts with everyone in the class.
  5. Compile their suggestions on the board to provide a visual aid and eliminate duplication.
  6. Classify the students' suggestions into the following knowledge areas that they should continue to consider throughout the light properties unit: basic properties of light, laser types and applications, and the construction of a laser security system.


security system: 1. In computing, a system that enforces boundaries between computer networks. 2. An electrical device that sets off an alarm when enforced boundaries are encroached upon.


Activity Embedded Assessment

Participation Grade: While the class compiles their thoughts, consider students' individual contributions in formulating their daily participation grades.

Worksheet: Have students complete the activity worksheet. Review their answers to gauge their comprehension of the material covered.

Investigating Questions

  1. What types of security systems would be candidates for protecting the mummified troll?
  2. What do you already know about how such security systems work?
  3. What do you know about light properties that would affect tripping a light-based security system?
  4. What must you learn in order to devise a security system for the troll's home?

Activity Extensions

If students show an interest in the logistics of the home security system, contact local companies to seek a demonstration of tripping window sensors, door sensors etc.

Activity Scaling

  • For lower grades, allow more time for group discussion.
  • For upper grades, ask further investigating questions with respect to laser security systems and light properties that may apply.


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Dictionary.com. Lexico Publishing Group, LLC. Accessed December 28, 2008. (Source of vocabulary definitions, with some adaptation)


© 2013 by Regents of the University of Colorado; original © 2008 Vanderbilt University


Terry Carter; Meghan Murphy

Supporting Program

VU Bioengineering RET Program, School of Engineering, Vanderbilt University


The contents of this digital library curriculum were developed under National Science Foundation RET grant nos. 0338092 and 0742871. However, these contents do not necessarily represent the policies of the NSF, and you should not assume endorsement by the federal government.

Last modified: November 22, 2019

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