Students answer questions correctly to collect treasure from the bottom of the ocean floor. Each piece of treasure is worth different amounts of points depending on its size and colour. With each correct answer, students reel in more rewards—who will finish with the greatest total?

In this version, students are presented with a range of composite shapes made from straight-sided figures. Each shape includes side measurements in metres (m), centimetres (cm), or millimetres (mm). Students must calculate the total perimeter by adding the given values together, helping them develop their understanding of measurement, unit conversion, and problem-solving strategies.

Let’s Sail – Calculating the Perimeter of Composite Shapes is perfect for Year 4–6 students learning how to apply perimeter skills in more complex and realistic scenarios. It’s ideal for maths rotations, independent practise, or as a high-engagement reinforcement activity using the QR code.

Key Learning Outcomes:

• ✅ Calculate the perimeter of composite shapes
• ✅ Work with metric units: metres, centimetres, and millimetres
• ✅ Apply addition strategies to multi-step measurement problems
• ✅ Strengthen unit conversion and geometry understanding
• ✅ Engage in interactive, reward-based gameplay to reinforce concepts

How to Play:

1. Students are presented with a composite shape and a list of side lengths.
2. They calculate the total perimeter by adding all the given side lengths.
3. Each correct answer earns a piece of treasure—some more valuable than others!
4. Occasionally, a surprise treasure chest may appear with bonus points.
5. The player with the highest treasure value at the end of the game wins!

Ideas for Classroom Use:

• 💡 Use during perimeter or measurement units for fluency and reinforcement
• 💡 Great for Year 4–6 students practising composite shape perimeter problems
• 💡 Add to rotations or as an extension task for early finishers
• 💡 Follow up with student-designed composite shapes to measure and label

Top Teacher Tips:

• 💛 Let students personalise their experience by choosing from six characters before the game begins
• 💛 Select the number of players or teams at the start of the game to suit individual, paired, or group play
• 💛 Send the QR code home for students to play as a homework or revision task

Let’s Sail – Calculating the Perimeter of Composite Shapes turns a key measurement concept into an engaging ocean adventure—where accuracy adds up to victory!