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After reading the story "Dear Mr. Henshaw" by Beverly Cleary, students create an alarm system for something in the classroom, just as the main character Leigh does to protect his lunchbox from thieves. Students learn about alarms and use their creativity to devise an alarm system to protect their lockers, desk, or classroom door. Note: this activity can also be done without reading "Dear Mr. Henshaw."

Engineers are continually confronted with challenges to solve as thoroughly as possible. Typically they start with a simple solution and then redesign it in order to make the solution more reliable and efficient. Sometimes engineers are lucky and get it right the first time, but it is more typical for a product to go through several redesign phases to improve the product. alarm brainstorming design teamwork The importance of alarm systems and where they are found. How to work in teams, with members having different roles. Design techniques and construction methods. Understanding the importance of cause and effect when designing an alarm. small bells (inexpensive) string elastics balloons wires marbles paper towel tubes pipe cleaners Popsicle sticks paper cups duct tape typical classroom supplies (such as paper clips, paper, tape, glue, erasers, scissors, etc.) What is the purpose of a car alarm? (Listen to student ideas.) It helps prevent thieves from stealing your car by triggering a loud alarm and drawing attention to the scene. How would you protect something that is valuable to you from being stolen if you were unable to watch it at all times? As an engineer, you must think of creative ways for protecting your locker, desk, or classroom door. Can you create a set of booby traps that will alert you if someone is trying to break in? Engineers usually work in teams. The advantage of working in a team is that everyone's ideas can be combined to come up with a great idea. This concept of sharing ideas is called brainstorming. To plan and make something in a skillful way. An alarm is a device that warns or signals, as by a bell, buzzer, or whistle. Alarms work by having some type of unwanted action set them off. Alarms take many forms. Some examples include: fire alarms, car alarms, alarm clocks, and security alarms. Recommended Resources: Inside a wind-up alarm clock. Good step-by-step pictures of a wind-up alarm clock. Shows inner workings of clock, including gears.: http://electronics.howstuffworks.com/gadgets/clocks-watches/inside-clock.htm History of time-keeping devices. Ancient Greeks introduced alarm clocks using water.: http://en.wikipedia.org/wiki/History_of_timekeeping_devices How digital clocks work: http://electronics.howstuffworks.com/gadgets/clocks-watches/digital-clock.htm Gather materials to be used by students to build alarms. Introduce the topic of alarms to students. Discuss the use of alarms in our daily lives and where they are found. If using the book, "Dear Mr. Henshaw," discuss why Leigh built an alarm. Explain to the students the goal: To build an alarm system to protect something in the classroom using only the materials provided. For example, build alarms to protect the students' lockers, desks, backpacks, the classroom door, or a window. Identify the materials available to the students. Discuss any safety concerns related to the materials being used. Explain that the alarm system must consist of at least three steps, and should use the least amount of materials as possible. Talk about and explain what a design is and why it is important. Explain your criteria for the grading of their designs. NOTE: you may want to begin with a one-step alarm, and make it more challenging by adding steps. Divide the class into groups of 3 or 4 students each. Direct them to work collaboratively accomplish the task of building an alarm. Ask students to draw on paper the design of their alarm system, including an explanation describing what their alarm does, how it works, and materials used. Have groups present their final products to the class and explain how they work.Give time for feedback and suggestions for improvement. Group Worksheet (doc) Group Worksheet (pdf) What are alarms used for? Why do we need alarms? Where do we find alarms? Why did Leigh in "Dear Mr. Henshaw" need an alarm? What do most alarms have in common? What might we need an alarm for in the classroom? Rubric for Performance Assessment (doc) Rubric for Performance Assessment (pdf) Dear Mr. Henshaw Cleary, Beverly. Dear Mr. Henshaw. Camelot, New York, New York. 2000.