ALEX Lesson Plan


Pizza Problems: An Angle Investigation

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  This lesson provided by:  
Author:Tim McKenzie
  General Lesson Information  
Lesson Plan ID: 33213


Pizza Problems: An Angle Investigation


This investigative lesson allows students to identify angle measurements as part of a larger angle. Students will deconstruct 180 degree angles into equal parts. 

This is a College- and Career-Ready Standards showcase lesson plan.

 Associated Standards and Objectives 
Content Standard(s):
MA2015 (4)
23. Recognize angles as geometric shapes that are formed wherever two rays share a common endpoint, and understand concepts of angle measurement. [4-MD5]
a. An angle is measured with reference to a circle with its center at the common endpoint of the rays by considering the fraction of the circular arc between the points where the two rays intersect the circle. An angle that turns through 1/360 of a circle is called a "one-degree angle" and can be used to measure angles. [4-MD5a]
b. An angle that turns through n one-degree angles is said to have an angle measure of n degrees. [4-MD5b]
MA2015 (4)
24. Measure angles in whole-number degrees using a protractor. Sketch angles of specified measure. [4-MD6]
MA2015 (4)
25. Recognize angle measure as additive. When an angle is decomposed into nonoverlapping parts, the angle measure of the whole is the sum of the angle measures of the parts. Solve addition and subtraction problems to find unknown angles on a diagram in real-world or mathematical problems, e.g., by using an equation with a symbol for the unknown angle measure. [4-MD7]

Local/National Standards:

Math Practice Standards:

1. Make sense of problems and persevere in solving them.

2. Reason abstractly and quantitatively.

3. Construct viable arguments and critique the reasoning of others.

4. Model with mathematics.

5. Use appropriate tools strategically.

6. Attend to precision.

7. Look for an make use of structure.

8. Look for and express regularity in repeated reasoning.

Primary Learning Objective(s):

I CAN identify approximate angle measurements.

I CAN measure angles with a protractor.

I CAN recognize smaller angles as additives of larger angles.

Additional Learning Objective(s):

 Preparation Information 

Total Duration:

31 to 60 Minutes

Materials and Resources:

Student Name Sticks (student names on pieces of paper is fine), Large Pizzas cut in half (each group will get half of a pizza, be sure to ask the pizza company to only cut the pizzas in half), Pizza slicers (enough for each group, or teacher can choose to be the one to cut the pizza), Chart paper, Pizza Angles activity guide, Math Toolbox which include the following: pencil, paper, graph paper, markers, scissors, glue, calculator, sticky notes

Technology Resources Needed:

Interactive Whiteboard (Optional) with required software, Document camera, projector


The teacher must order the appropriate number of pizzas for the class (see details in the materials section).

The teacher must make the appropriate number of copies of the Pizza Angles activity guide (found in attachments). Copies should be made so that students can work collaboratively. 

Students must have knowledge of angle measurements.


1.  The teacher will launch the investigation by asking, "WHO LIKES PIZZA?" "Who always tries to pick their piece first so that they get the biggest piece?" "Why are their different sized pieces in the pizza box?" Responses will vary, the point is to spawn excitement for student engagment.

2.  The teacher will lead a discussion on angles found in pizza. "Based on what you know about angles, what measurement is a Pizza?" Ideal response "360 degrees." The teacher may ask, "What are some equal angles you can make in 360 degrees?" Ideal response, "four 90 degree angles, ten 36 degree angles, etc."

3.  The teacher will transition to the activity explaining that each group will be getting one half of a pizza. However, each group will be a different size. (Groups will vary depending on size, I recommend not going over 5 students per group and no less than 3.)

4.  The teacher will inform the students that some groups will have 3 people, 4 people, or 5 people. The teacher will proceed to draw names to put students in appropriate groups (drawing names makes the activity as fair as possible). 

5.  Once in groups students will complete the activity. Students may not get their actual pizza until they can decide how much each person can get.

6.  As students are engaged in the investigative activity, the teacher will act as facilitator and coach by asking questions that drive instruction. How do you know each person gets that angle? How did you do ______?

7.  Once the activity is completed, the students will present their finding (and of course enjoy their portion of pizza). As they are presenting the teacher will ask questions to spawn thinking as need be. Who was in the best group? Why is it better to be in a group with less people?

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Assessment Strategies

Informal Formative Assessment: As the students are working the teacher will act as the facilitator and coach. Teacher will ask questions to evaluate students (i.e. How do you know ______? What did you do to get that?) Teacher may pull small groups during investigation on a needs basis.

Formal Formative Assessment: Using the Investigative Activity Rubric (found in attachments) students will be evaluated on their finish group project. 


An extension is included on the Pizza Problem Activity guide.


Struggling students should be grouped with a peer tutor and teacher should pay close attention to the those groups to assure complete understanding.

Each area below is a direct link to general teaching strategies/classroom accommodations for students with identified learning and/or behavior problems such as: reading or math performance below grade level; test or classroom assignments/quizzes at a failing level; failure to complete assignments independently; difficulty with short-term memory, abstract concepts, staying on task, or following directions; poor peer interaction or temper tantrums, and other learning or behavior problems.

Presentation of Material Environment
Time Demands Materials
Attention Using Groups and Peers
Assisting the Reluctant Starter Dealing with Inappropriate Behavior
Be sure to check the student's IEP for specific accommodations.