Activity: Make an Alarm! (Can be used in conjunction with "Dear Mr. Henshaw")



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

LEVEL OF DIFFICULTY [1 = Least Difficult : 5 = Most Difficult]

5-most difficult (can be modified)


40 minutes (one class period)


$10 (approximately $1 per group, use materials already found in classroom)


1.1 Identify materials used to accomplish a design task based on a specific property, i.e. weight, strength, hardness, and flexibility.
2.1 Identify a problem that reflects the need for shelter, storage, or convenience.
2.2 Describe different ways in which a problem can be represented, e.g., sketches, diagrams, graphic organizers, and lists.
2.3 Identify relevant design features (e.g., size, shape, weight) for building a prototype of a solution to a given problem.

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

Design: 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. They work by having some type of unwanted action set them off. There are many different types of alarms. Some examples are: fire alarms, car alarms, alarm clocks, and security alarms.
RESOURCES: -Good step-by-step pictures of a wind-up alarm clock. Shows inner workings of clock including gears - Ancient Greeks introduced alarm clocks using water - General History of clocks, including early candle alarm clock - How a Digital clock works

Small bells (inexpensive)
Papertowel tubes
Pipe cleaners
Popsicle sticks
Paper cups
Duct tape
Typical classroom supplies (such as paper clips, paper, tape, glue, erasers, scissors, etc.)
Teacher should gather materials to be used by students to build the alarms.


1. Introduce the topic of alarms to the 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.
2. Explain to the students their goal. They must build an alarm system to protect something in the classroom using only the materials that the teacher gives them. Some ideas are to build alarms to protect the students' lockers, desks, backpacks, the classroom door, and a window.
3. Identify the materials available to the students. Discuss any safety concerns that should be considered with these 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: the teacher may want to begin with a one step alarm, and make it more challenging by adding steps.
4. Break the students up into groups of 3 or 4. They should collaboratively accomplish the task of building an alarm.
5. Students should draw the design of their alarm system on paper. There should be an explanation describing what their alarm does, how it works, and what materials were used.
6. Each group should present their final products to the class and explain how it works.

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 you need an alarm for in the classroom?
Cleary, Beverly. Dear Mr. Henshaw. Camelot, New York, New York. 2000.


See Associated Download.


See Associated Download.