Give your coordinate geometry lesson a twist of mystery and fun! This Midpoint Formula Decode the Mystery Number activity helps students review and practice applying or using the midpoint formula, but with a code-breaking twist that keeps them engaged from start to finish. Each correct answer unlocks a code, and once all eight problems are solved, students add the codes to reveal a mystery number that must match a set of clues.

It’s a creative, no-prep way to reinforce midpoint concepts while building problem-solving confidence and a bit of excitement into your math class.

✅ What's Included:

• 3 different versions of the mystery number activity
• Cipher table + clues to solve
• Full answer keys for easy checking

Use this engaging and versatile activity for independent practice, math centers, partner work, review stations, early finishers, or sub plans.

✏️ How It Works:

1. Students read the clue to guess what kind of number they’re hunting for.
2. They solve 8 midpoint formula problems—no shortcuts allowed!
3. Next, they decode their answers using the cipher table to reveal hidden numbers.
4. Add ‘em up... and if they cracked it right, the final total matches the clue!
   

Note: These worksheets don’t include workspace, but students can show their work on notebook paper (you know they should anyway!).

⭐️ Great For:

• Independent work or math centers
• Partner practice or early finishers
• Review days, sub plans, or just mixing things up!

These printable algebra worksheets are a great way to sneak in practice while keeping things light and engaging.

❤️ Love this resource?

Check out our full “Decode a Mystery Number” collection for more topics your students will love!

• Absolute Value Equations {Decode a Mystery Number}
• Determinant of a 2x2 Matrix {Decode a Mystery Number}
• Distance Formula {Decode a Mystery Number}
• Factoring Trinomials {Decode a Mystery Number}
• Logarithmic Equations {Decode a Mystery Number}
• Midpoint Formula {Decode a Mystery Number}
• Multi-Step Equations {Decode a Mystery Number}
• Proportions {Decode a Mystery Number}
• Quadratic Equations {Decode a Mystery Number}
• Radical Equations {Decode a Mystery Number}
• Rational Equations {Decode a Mystery Number}
• Radical Expressions {Decode a Mystery Number}
• Slope Formula {Decode a Mystery Number}
• Systems of Equations {Decode a Mystery Number}
• Two-Step Equations {Decode a Mystery Number}

We hope that you and your students enjoy this Decode a Mystery Number activity. Our goal is to create quality math resources that will be helpful in your class instruction. If you found any errors/typos or have any questions about this product, please don’t hesitate to contact us at tpt@chilimath.com. Thank you!

Mike and Kathy

© ChiliMath, 2016 - present. The purchase of this product entitles the buyer a limited individual license and is non-transferable. This product is intended to be used by one teacher only. If you would like to share this math resource with your colleagues, you may revisit our TpT store and purchase additional licenses at a discounted price. This product may be printed or photocopied but may not be sold, transmitted, or put on the internet/intranet without a written permission from the authors. Thank you for respecting our work!