Foundations of Mathematical Thinking · Junior Infants

Active learning ideas

Surface Area of Prisms

Active, hands-on experiences help young learners connect abstract ideas to real objects. Building prisms with blocks and wrapping them with fabric makes surface area concrete and visible. This tactile approach builds lasting intuition about covering three-dimensional shapes.

• NCCA Curriculum Specifications
• NCCA: Junior Cycle - Strand 3: Measurement - M.1.5

• 20–35 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Collaborative Problem-Solving
• 35 min · Small Groups

Building Stations: Prism Nets

Provide multilink cubes for students to build rectangular and triangular prisms at stations. Unfold each into a net and cover faces with sticky notes or counters. Groups record total coverings and compare with peers.

Explain how a net helps in calculating the surface area of a prism.

Facilitation Tip

During Building Stations: Prism Nets, circulate with a checklist to note which students count faces systematically and which miss hidden sides.

What to look for

Provide students with pre-drawn nets of simple rectangular prisms. Ask them to count the number of faces and label each face with its dimensions (e.g., 3x2). Then, have them write an addition sentence to find the total area of the faces.

• Apply
• Analyze
• Evaluate
• Create
• Relationship Skills
• Decision-Making
• Self-Management

Activity 02

• Collaborative Problem-Solving
• 25 min · Pairs

Pair Wrap: Gift Box Challenge

Pairs build a small rectangular prism from blocks, then wrap it with colored paper, cutting pieces to fit each face without overlap. They count paper squares used and discuss why all faces need covering.

Justify the formula for the surface area of a rectangular prism.

Facilitation Tip

In Pair Wrap: Gift Box Challenge, prompt pairs to verbalize their steps aloud so you can hear their reasoning about covering all faces.

What to look for

Present students with a picture of a gift-wrapped box. Ask: 'If we wanted to know how much wrapping paper was used, what would we need to calculate? How could we figure that out using the box?' Guide them to connect the wrapping paper to the surface area.

• Apply
• Analyze
• Evaluate
• Create
• Relationship Skills
• Decision-Making
• Self-Management

Activity 03

• Collaborative Problem-Solving
• 30 min · Whole Class

Whole Class: Net Matching Game

Display printed nets around the room. Students hunt for matching prisms built from blocks, then calculate surface by adding face areas using a class chart. Share one real-world example each.

Design a real-world problem that requires calculating surface area (e.g., painting a box).

Facilitation Tip

For Whole Class: Net Matching Game, use a timer to keep the matching fast-paced and observe which students quickly visualize folds.

What to look for

Give each student a small, empty box (like a tissue box or cereal box). Ask them to draw the net of the box on one side of the paper and then write down the dimensions of each face. Finally, ask them to write an addition sentence showing how they would calculate the total surface area.

• Apply
• Analyze
• Evaluate
• Create
• Relationship Skills
• Decision-Making
• Self-Management

Activity 04

• Collaborative Problem-Solving
• 20 min · Individual

Individual Explore: Playdough Prisms

Each student molds playdough into a prism, presses it onto paper to make a net outline, and fills with counters. They label faces and add totals, then share with a partner.

Explain how a net helps in calculating the surface area of a prism.

Facilitation Tip

During Individual Explore: Playdough Prisms, ask students to press unit cubes onto each face to reinforce measuring area, not volume.

What to look for

Provide students with pre-drawn nets of simple rectangular prisms. Ask them to count the number of faces and label each face with its dimensions (e.g., 3x2). Then, have them write an addition sentence to find the total area of the faces.

• Apply
• Analyze
• Evaluate
• Create
• Relationship Skills
• Decision-Making
• Self-Management

A few notes on teaching this unit

Teachers guide students to move from concrete to pictorial understanding before abstract calculation. Start with physical blocks and nets, then shift to drawings and addition sentences. Avoid rushing to formulas; instead, emphasize counting and covering faces to build strong spatial reasoning. Research shows that young learners develop geometric concepts best when they manipulate materials and discuss their observations.

Students will accurately count faces, measure each face with unit squares, and add the totals to find surface area. They will explain why every face matters and how nets represent the full shape. Confidence grows as they connect 2D nets to 3D prisms through folding and wrapping.

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Watch Out for These Misconceptions

• During Building Stations: Prism Nets, watch for students who only count the top and bottom faces of their prism.

  Ask them to unfold the net and press unit squares onto every face, including the sides. Guide them to recount aloud, pointing to each face as they cover it.

• During Whole Class: Net Matching Game, watch for students who struggle to match nets to their prisms.

  Have them use cardstock nets and fold them slowly, testing each face against the prism. Encourage peer support to reinforce the connection between 2D and 3D.

• During Pair Wrap: Gift Box Challenge, watch for students who confuse surface area with volume.

  After wrapping the box, fill it with small objects like buttons and ask if the amount of fabric changed. Discuss how covering the outside differs from filling the inside.

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Methods used in this brief

• Collaborative Problem-Solving