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Shape Up

  • Lesson
Terry Johanson
Langham, SK, Canada

Students hear geometry terminology around them every day.  By playing the games in this lesson, students use their knowledge regarding regular and irregular polygons to explore the properties of the shapes and learn new vocabulary when identifying characteristics of shapes.

The following activity ideas are written as either teacher-centered or small group/pair activities. All activities could be adapted to be either type. Depending on student knowledge, there are certainly sections that can be repeated and others than can be skipped. You can choose a flexible path through the instructional plan to best meet the needs of your students.

Students are to work in pairs or small groups. In some cases, the pair will need to have 2 sets of shapes. In others, the pair will need to have 1 set of shapes. If you are photocopying sets of shapes from the Shape Up Shapes activity sheet, a suggestion is to copy them onto a variety of colors of paper so that sets within the same pair of students are different so they can maintain their own set without getting mixed up. Students can cut their own set of shapes out.

pdficon Shape Up Shapes Activity Sheet 

Begin by modeling at least one activity for the class. Figure out a way that you can display one set of sorting shapes at the front of the room. The easiest way to accomplish this is by displaying the Shape Sorter tool for all the students to see. Alternatively, this could be done with sticky tack, tape, magnets, tacks, or magnetic clips.

appicon Shape Sorter Tool 

While the games are being played, keep a word wall of geometry terms that will grow throughout the activities that students participate in. These terms should also be recorded on the Shape Up activity sheet.

pdficon Shape Up Activity Sheet 

Yes and No 

Choose one characteristic that you will use to classify all of the shapes. This could be one of the characteristics listed on the Shape Up Characteristics activity sheet. Set up a yes-and-no sorting mat or T chart at the front of the room. Silently sort the shapes onto the Yes and No mats. Have students try to guess what the characteristic is that you used to sort the shapes.

pdficon Shape Up Characterstics Activity Sheet 

Here is an example:

2989 yes no 

The characteristic used to classify shapes is: At least one angle is a reflex angle

Students may describe the shape using its characteristics, such as "All the Yes shapes have corners that go in." If this is the case, it is an opportunity for you to introduce the term reflex angle, which is an angle whose measure is greater than 180°.

Guess What 

All students will need their own set of sorting shapes. Secretly hide one of the shapes (put it into a drawer or envelope). Your students will now ask you yes or no questions. When a question is asked, write it at the front of the room or on an overhead. Answer the question. Students are to remove all of the shapes that do not satisfy the answer you gave them. This continues until one student guesses the correct shape.

Here’s an example: You have chosen an equilateral triangle as your secret shape. One student asks, "Does it have 4 sides?" You answer, "No." The entire class removes all shapes with 4 sides from their sets of shapes. The next student asks, "Are all of the sides congruent?” You answer, "Yes," and the entire class removes all shapes with non-congruent sides from their sets. This continues until someone correctly guesses the secret shape.

If after the game, there are some students that did not have the correct shape still on their desks, go back through the questions on the board and have them figure out what characteristic they did not understand.

At Their Desks 

The following are games that could be played by pairs or small groups using their sorting shapes. They can be played in any order for a length of time determined by the teacher. A suggestion is to play games for one class period, and then have them play one game as a lesson opener at various times throughout the year or unit. In any game, students are to write down new terms on the Shape Up activity sheet. These terms will then be added to the word wall near the end of the class.

I Am a... 

  • played in groups of 4 split into 2 teams of 2
  • one set of sorting shapes per large group

Each team will take turns playing. Each group should spread out all the shapes on the table. The first team will choose one person who will be the describer. That person will choose a secret shape from the set of sorting shape. The describer can state up to three clear statements that describe the shape they have chosen. Encourage students to use geometry vocabulary, but also use more common wording if they don’t know if their partner is familiar with a given term. For instance, if the describes chooses a regular pentagon, then the statements might be:

  • It is a pentagon.
  • It has five sides.
  • All of the sides have equal lengths.

The describer's partner can then try to guess what shape the describer has chosen. If they guess regular pentagon correctly, that team gets to keep that sorting shape. If they guessed another shape, the opponent team has a chance to steal the shape by guessing. If they also choose incorrectly, the shape stays on the table. It is now the other team’s turn. Play continues until all of the shapes are gone.

Sometimes, Always, Never 

  • Played in pairs
  • One set of sorting shapes per pair
  • Each pair should have a Shape Up Sorting Chart activity sheet
pdficon Shape Up Sorting Chart Activity Sheet 

Have each pair of students choose a type of polygon (e.g., rectangle, parallelogram, or triangle). These can be customized to the types of polygons relevant to your class. Students will then identify all of the sorting shapes that fall into their category. From there, students are to identify characteristics that are always true and sometimes true for the type of polygon they have chosen. They can then look at those shapes that do not.

Sorting Sets 

  • Played in pairs
  • One set of sorting shapes per pair
  • One computer with Internet access per pair
  • Shape Sorter tool

Each pair will choose 2 rules at the bottom of the online tool. As a team, players should decide whether they're going to sort all the shapes for that pair of rules or a predetermined number (e.g., 5 turns each). Players play the game by taking turns moving a single shape into the correct area of the board. When they are finished, they can click the check mark to check their answers. Correctly sorted shapes will be highlighted in blue. Incorrectly sorted shapes will be highlighted in pink. The player with the most shapes highlighted in blue wins.

Reflecting on What They Have Learned 

After your class has had an opportunity to play one or more of the Shape Up games, they should reflect on the geometry vocabulary that they used and learned from their peers. This can be done by having students add terms to a geometry word wall.

Have the class brainstorm all new words that don’t already exist on the word wall. This will be particularly easy the first time students go through this process, as the word wall will be blank. The challenge for students in subsequent classes would be to make sure that they think of at least one new word that is not on the word wall so that they can keep adding to it.

If you would prefer, you could have students add to the geometry word wall by assigning or having students volunteer to create the new entries for the wall. Each entry should have the word, a definition, and a sketch. This is similar information to what students have completed on their student activity sheet.

When your word wall has a few words added, you can use it as an extra challenge in subsequent games. For instance, if one of the words on the word wall is parallel, then teams can keep score of how many times they use the word parallel correctly while playing the game. These scores could be shared during their reflection time.



  1. Choose 2 sorting shapes, and trace them onto a separate piece of paper. Ask students to describe how they are the same and different by listing as many characteristics as possible.
  2. Describe or have a student describe three characteristics of a polygon and asks the class to draw a polygon that might match the description.


    • Draw a pentagon with at least one pair of parallel lines and at least one right angle.
    • Draw a polygon with one reflex angle, at least four sides, and at least one pair of parallel lines.
  3. Encourage creative thinking by having students brainstorm shapes not in the set of sorting shapes provided that would have been good to add to the set. Have students write a journal entry including a sketch of the shape and the reasons why they think their shape would make a good addition. You could also ask them about additional characteristics that could be included in the games.


  1. To extend the students knowledge, assign each pair of students a different sorting shape, and assign them the task of creating a list of 3 clues for their shape at home. This can be written on a 3x5 index card. Have students write the clues increasingly more specific as they move from the first to the second to the third.
  2. Create new characteristics or new shapes that are not included in the original card set. Use these to play, along with the original cards and shapes. For example, you might choose to include 2-dimemsional closed figures that aren't polygons, such as circles.

Questions for Students 

1. What vocabulary did you learn by playing each of the Shape Up games? What vocabulary were you already familiar with?

[Answers will vary. Encourage students as their playing their games to focus on the vocabulary they are using.]

2. What shapes were most easily identified by each characteristics? Why would this be?

[Generally speaking, characteristics that only apply to a few shapes make the sorting games easiest.]

3. Were there some shapes that are harder to distinguish between than others? Why would this be?

[While the question is a matter of opinion, most students will probably answer yes to this question. Shapes that share many characterstics are harder to distinguish from one another. For example, the isosceles and non-isosceles trapezoids.]

Teacher Reflection  

  • Did students use geometry terms while playing the games? If not, how could their use be encouraged more in your classroom?
  • Was your lesson appropriately adapted for the diverse learner?
  • How did your lesson address auditory learning styles?
  • How did the students demonstrate understanding of geometry terms?     

Learning Objectives

Students will:

  • Identify and describe characteristics of geometric figures
  • Compare the properties of geometric figures
  • Understand terminology related to geometric figures

Common Core State Standards – Mathematics

Grade 5, Geometry

  • CCSS.Math.Content.5.G.B.3
    Understand that attributes belonging to a category of two-dimensional figures also belong to all subcategories of that category. For example, all rectangles have four right angles and squares are rectangles, so all squares have four right angles.

Grade 5, Geometry

  • CCSS.Math.Content.5.G.B.4
    Classify two-dimensional figures in a hierarchy based on properties.

Common Core State Standards – Practice

  • CCSS.Math.Practice.MP1
    Make sense of problems and persevere in solving them.
  • CCSS.Math.Practice.MP4
    Model with mathematics.
  • CCSS.Math.Practice.MP5
    Use appropriate tools strategically.
  • CCSS.Math.Practice.MP7
    Look for and make use of structure.