top of page

MathBait™ Multiplication Part 6: Playing with Napier's Bones

Updated: Apr 14

Welcome to MathBait™ Multiplication Part 6, the penultimate unit in our multiplication series. In the previous unit, we introduced Napier's Bones, an exciting way to increase fluency and focus on structure to prepare students for multi-digit multiplication. Now that students have a set of bones and know how to use them, it's time to play! Below, we provide 10 hands-on activities to help you make the most out of Napier's Bones. We do not include any digital activities in this unit as we want students to play with physical bones to help build familiarity and fluency. Don't worry, the activities below are low-entry/high-ceiling, full of fun, and all contain our unique methods to ramp up engagement with students! Plus, we'll be back next week to wrap up MathBait™ Multiplication with some amazing activities and digital games focusing on prime numbers.


Many of the games and activities below can be played with students of any age, so long as they can recognize digits. We focus here on playing with rods to increase exposure as well as look for and recognize patterns. However, for the biggest bang, we recommend students first complete MathBait™ Multiplication Parts 1-3 and have at least created their own set of bones (for step-by-step instructions see MathBait™ Multiplication Part 5).


The lessons and activities below allow students to informally play with numbers. Through exposure to Napier's Bones they are becoming more fluent and beginning to pick up on smaller nuances and patterns, as well as the structure of numbers. We recommend spiraling back to games in earlier units as you explore different ways to interact with your multiplication rods.

Each tab below contains a single game or activity that can be played with Napier's Bones. We go from simple explorations to strategy games that can be great for students through high school.

Do You Know My Rod?

This is a great activity for younger students just learning about multiplication.

Distribute a set of bones to each student. Teachers may also allow students to share a set at a table or in a small group and/or project a set of bones to the class.

Explain to students they will be going on a scavenger hunt. Teachers will provide two values. Students should try to find both values on one rod.

Tell students you are thinking of a rod that contains the numbers 4 and 8; can they find it? Allow students time to examine the bones in their set to find one that contains both numbers. Allow students to share what they found. Some students may have collected the 2 bone, others may have collected the 4 bone, other possible bones are 1,3, 6, 7, 8, or 9. Allow students with unique bones to share.

Ask students what bones do not contain the digits 4 and 8 (only 5) and prompt them to consider why this is. (All the multiples of 5 end in a 0 or 5, so there are no other one's place values. As the rods only go up to 9, and 9×5=45, there is a 4 but there is not enough values to also have an 8 in the ten's place.) Encourage students to determine how big their rod must be so that the 5 would have both a 4 and an 8. (The first 8 in the ten's place would be 80. Look for different ways to determine what multiple of 5 this must be. For instance, a student may notice 80=8×10=8×2×5, and thus 16×5 must equal 80. A 5-rod would need to go up to 16 to include both a 4 and an 8.)

Circle back to your rod. Announce the rod you are thinking of contains the number 4 (displayed on a rod as 04) and the number 8 (08) (rather than simply the digits 4 and 8), can students find your rod? Students should now be able to throw out all rods except 1, 2, and 4. Model a systemic logical approach by asking students to explain, in order, the rods we know it cannot be. For instance, we can throw out all rods above 5, as 5×1 is more than 4 (as is 6×1, 7×1, etc.) so none of these rods could possibly contain the value 4. We are left with 1, 2, 3, and 4. We can also throw out 3 because we know skip counting by 3's skips over 4. Checking the final rods 1, 2, and 4 we see that each contain the values 4 and 8.

In the next activity, students will build on this exploration to make combinations that are possible or impossible. These activities are helping students build number sense while also developing more familiarity with the multiplication table/rods.

Possible or Impossible?


The Maze

The Bone Collector

Secret Codes

Fast Adding

Guess Who

Who Did It?



In MathBait™ Multiplication Part 6, we have provided 10 fun games and activities for use with Napier's Bones. Using the rods, students are building familiarity and exposure to multiples and products. As they play detective, hunt for values, look for patterns, or try to create target numbers, students are focusing on the structure and applying reasoning and problem solving. Each of these activities is easy to play, super engaging for students, and will build both confidence and understanding. We hope you have a blast with these activities and share your experiences with us.

Next week sees MathBait™ Multiplication come to a close. With all new lessons, activities, and digital games, we will target factoring and prime numbers. Factoring is a key skill as it helps students to understand how to take apart and rearrange products, leading to improved fluency. It is also vital for fractions, GCF, LCM, and into algebra for working with polynomials and radicals. We will show you how teaching your students to factor early will not only help strengthen their multiplication, but also help students to see numbers as able to be manipulated, leading to enhanced problem solving skills and outcomes. And of course, we'll do it all through fun and engaging activities like only MathBait™ can!

NOTE: The re-posting of materials (in part or whole) from this site is a copyright violation! We encourage you to use these activities with your students. You can not take any part of these activities and post them as your own or crediting MathBait™ without written permission. This includes making derivatives for Teacher Pay Teacher or other websites. The material here is not considered "fair use". Thank you for respecting the author's rights.


Commenting has been turned off.
© MathBait

Thank you for visiting MathBait™! We would like to remind our visitors that we encourage the use of this material when working with students. However, our publications are not considered fair right. All the material on this website is copyrighted and cannot be copied or re-posted for commercial or non-commercial purposes without our permission. Thank you for your understanding and cooperation.

bottom of page