Camping Choices

Explaining and justifying
Representing and connecting
  • Geometry
  • Measurement
  • Multiplication
Grade level
Use an App
Number Pieces
Number Pieces
geoboard icon

What tent size is big enough for 4 people?

A tent

Cori and three friends are going camping. 

  • They will share one tent, and they want a large enough tent to fit just their sleeping bags. 
  • Their sleeping bags are rectangular and all the same size.
  • When purchasing a tent, the package is labeled with the dimensions of the rectangular base. 

What size of tent should they buy? What could the dimensions of the rectangular base be? What could the area of the base be? 

How could you get started?
  • How much space would one sleeping bag require? What are the typical dimensions for a sleeping bag?
  • How could you represent this situation?
Ready to explore more?
  • Why is it important that we consider the dimensions and not just the area of the tent base when making a recommendation? 
  • Use the internet to look at tents that are available for sale at stores near you. Would any of them meet the needs of Cori and her friends? Which one would you recommend they purchase? 
  • If a group of 30 friends were going camping, what size tents would you recommend they purchase? How many of them would they need? 
For Teachers: More about this activity

In this task, students will use their understanding of area and perimeter to make recommendations about the dimensions of the space needed and the size of the tent that is necessary for four sleeping bags. Area and perimeter are measurements of two-dimensional figures that quantify a physical space. Understanding these measurements provides the foundation for developing further understanding of geometric measurements, such as volume. 

Students will need to make assumptions about the amount of space each person would need for their sleeping bag and then use that assumption to determine how the sleeping bags would be organized. They may use their own height to help them estimate the dimensions of each sleeping bag. They will then need to consider the arrangement of each sleeping bag. They might arrange them in one or two rows. Those with experience camping might share that a sleeping bag is rectangular and that a long, thin tent is unlikely, so placing the sleeping bags in one row with the short dimensions touching (head-to-foot) doesn’t make sense. 

Students may choose to use an app to create a representation of the situation. 

  • They could use each unit in the Number Pieces app to represent one square foot in a sleeping bag model. They might determine the minimum dimensions of the tent using just the dimensions of the sleeping bags, or they might decide to leave additional space between the sleeping bags (as shown here). 
  • Alternatively, students might use the Geoboard app to represent the sleeping bags and tent dimensions (as shown here). 

No matter the app students choose to use, their response will depend on the assumptions they make regarding the dimensions of each sleeping bag, the arrangement of the sleeping bags within the tent, and whether there will be space between the sleeping bags. 

To push their thinking further, you might invite students to share with a partner and compare their responses and the assumptions that led them to their solution. Ask them to reflect on their assumptions and ask: What other tent dimensions might fit 4 sleeping bags? Additionally, you might want students to use their recommendations to explore this real-life scenario more deeply. Help them find tents that are currently being sold and advertised for 4 people. How do their recommendations compare to the dimensions of the tents for sale?