The Games Book Series · Stage 4 · Multiplicative Reasoning
100 Add or Multiply Beads · Split the Array
Blog 5 of 12
Deepening Multiplicative Reasoning with the Linear Abacus®:From Basic Operations to Mathematical Expression
When children can see what multiplication actually does to the beads, choosing the right operation stops being a guess.
Have you ever noticed how children reach a point where they can follow multiplication procedures but struggle to decide when to multiply versus when to add? Or perhaps your child can multiply small numbers but becomes overwhelmed when facing larger ones like 8 × 12? These challenges mark an important transition in mathematical development — moving from simply executing operations to understanding when and how to use them meaningfully.
In our previous blogs, we explored the foundations of number sense (Blog 1), place value (Blog 2), mental strategies for addition and subtraction (Blog 3), and number relationships through comparison, strategy, and equivalence (Blog 4). Now we’re ready to deepen this multiplicative journey through two powerful games: “100 Add or Multiply Beads” and “Split the Array.”
These games address a critical phase in mathematical development where children move beyond performing calculations to expressing mathematical ideas with purpose and meaning. Just as learning language isn’t just about vocabulary but about expressing thoughts, learning mathematics isn’t just about operations — it’s about developing ways to express quantitative thinking. Through the Linear Abacus®, children experience multiplication not as mysterious procedures but as meaningful actions they can see, touch, and describe in their own words.
This approach to mathematics reflects a deeper truth: when children learn to express mathematical ideas clearly, they’re not just gaining academic skills — they’re developing tools to participate in and shape the world around them.
The Mathematics
The Mathematics Behind the Games
As children move deeper into multiplicative reasoning, they face two significant challenges that these games directly address.
1. Distinguishing Between Additive and Multiplicative Situations
Children often struggle to recognise when a situation calls for multiplication rather than addition. This isn’t merely about calculating correctly but about interpreting real-world situations mathematically. Understanding that “5 packets with 3 lollies each” (multiplicative) is fundamentally different from “5 red lollies and 3 blue lollies” (additive) is visible on the Linear Abacus® in a way it can never be on a worksheet. What Fosnot and Franke independently observed about this distinction — that it is essential for mathematical modelling and problem-solving — confirms what the beads show from the first game: addition moves you along the string, n-folding creates a different structure entirely.
2. Developing Strategies for Larger Multiplications
When faced with larger numbers like 8 × 12, children who think of multiplication only as repeated addition quickly become overwhelmed. The distributive property — understanding that 8 × 12 can be broken into manageable parts like (8 × 10) + (8 × 2) — transforms complex multiplication from intimidating to visible. On the Linear Abacus®, this isn’t a rule to memorise. It’s what two rectangles placed side by side actually look like.
Game One
100 Add or Multiply Beads
During “100 Add or Multiply Beads”, the choice between adding and multiplying is not a guess — it’s a decision the child can see the consequences of before a single bead moves. That visibility is what makes the strategic thinking real.
Talk: Probing Questions
- “What do you notice about the answer when you multiply a single digit number by 10?”
- “How is adding 7 different from multiplying 7 by 10?”
- “Why did you choose to multiply/add in this situation?”
- “How does your choice help you get closer to 100?”
- “How can you explain what ‘seven 10-folded’ means?”
“You rolled a 6 and chose to multiply by 10 instead of adding 6. Can you explain your thinking?”
“If I just added 6, I’d only move a little bit. But if I multiply by 10, I get 60, which gets me much closer to 100.”
“That’s strategic thinking! Can you explain what ‘6 multiplied by 10’ means on the abacus?”
“It means I make 6-folds, 10 times. So I take 6 beads as a group, and I make 10 copies of that group.”
“That’s a powerful way to explain multiplication. You’re not just calculating — you’re thinking about what the operation actually means.”
This dialogue helps children see multiplication not just as a procedure but as a meaningful action with purpose — an expression of a specific mathematical idea.
Do: Mathematical Gestures
The physical manipulation in “100 Add or Multiply Beads” makes multiplicative thinking visible and tangible:
Write: Mathematical Symbolism
Recording the multiplicative thinking connects physical actions to mathematical expression:
For strategic decisions, encourage a simple recording that shows the number rolled, the choice made (add or multiply by 10), the resulting position, and the reasoning behind the choice. This documentation helps children reflect on the purposefulness of their decisions — when multiplication makes sense versus when addition is more appropriate.
Game Two
Split the Array
During “Split the Array”, the distributive property stops being a rule to follow and becomes something a child can see — two rectangles placed side by side, each one a part of the whole, both together confirming the answer.
Talk: Probing Questions
- “Does your model match your calculation?”
- “Could you have split the group or operator differently?”
- “How many ways could you do this? Which way helps you calculate mentally?”
- “How does splitting the numbers make multiplication easier?”
- “Can you explain why your strategy works?”
“You’re multiplying 8 × 12. How are you thinking about breaking this down?”
“I’m going to split 12 into 10 and 2.”
“Why did you choose to split it that way?”
“Because it’s easier to multiply by 10, and then I just need to add the 8 × 2 part.”
“That’s strategic thinking! Can you explain how your method works using the Linear Abacus®?”
“I’ll show 8 × 10 first, which is 80. Then I’ll show 8 × 2, which is 16. Then I combine them to get 96.”
Do: Mathematical Gestures
The physical manipulation in “Split the Array” makes the distributive property tangible:
This Level 3/4 student has chosen to make 3 × 8 an easier calculation by splitting the operator into (3 × 4) + (3 × 4). She notices the colour pattern on the beads for 12 — in the first rectangle 12 is shown as 10 + 2, and in the second rectangle it’s shown as 8 + 4. She mentions that colour makes adding the total easier: she can see 24.
Write: Mathematical Symbolism
Recording the multiplicative reasoning creates connections between physical actions and mathematical expressions:
Encouraging children to create multiple representations helps them see the connections between physical models and symbolic expressions, building a network of understanding rather than isolated procedures.
The Bigger Picture
Mathematics as Meaningful Expression
The progression from “100 Add or Multiply Beads” to “Split the Array” represents an important shift in how children experience mathematics — from executing procedures to expressing mathematical thinking. This parallels the development of language, where children move from using words to crafting meaningful sentences that express their thoughts.
When children engage with these games on the Linear Abacus®, they’re developing more than computational skills; they’re learning to:
This shift from procedure to expression is crucial for children’s mathematical development. It empowers children to use mathematics as a tool for making sense of the world.
Looking Back
The Sense-Making Journey Continues
As we’ve emphasised throughout our blogs on the Linear Abacus®, mathematical understanding develops most powerfully when children make sense of concepts through meaningful experiences. “100 Add or Multiply Beads” and “Split the Array” continue this sense-making journey by:
This sense-making approach transforms mathematics from a set of rules to be followed into a meaningful language for expressing ideas about the world — a transformation that opens doors to deeper mathematical understanding and fuller participation in our shared cultural conversation.
Beyond the Game
Extending Learning Beyond the Game
These multiplicative concepts can be reinforced through everyday activities:
- Shopping: “If one package costs $4 and we need 3 packages, how much will we spend?” (multiplicative situation)
- Cooking: “This recipe needs 6 eggs. If we make 5 batches, how many eggs will we need?” — try 5 × 6 = 5 × (5 + 1) = 25 + 5 = 30
- Home Projects: “If each shelf needs 8 screws, and we’re building 12 shelves, how many screws do we need?” — split 12 into 10 + 2 for easier calculation
- Time Management: “If your piano practice takes 15 minutes per day, how much time in a 7-day week?” — 7 × 15 can be split into 7 × 10 + 7 × 5
Look for opportunities to discuss the difference between additive and multiplicative situations, and to explore different ways of breaking down larger multiplications into manageable parts.
What to Look For
Parent Reflection Guide
Common misconceptions to watch for include: thinking of multiplication only as repeated addition without recognising its unique structure; splitting numbers without understanding why the decomposition works; following procedures without meaningful connection to the beads; rigidly using only one approach instead of flexibly choosing strategies.
What Independent Research Confirms
What Fosnot and Franke independently observed about children’s struggle to distinguish additive from multiplicative situations — that this distinction is essential for mathematical modelling — confirms what “100 Add or Multiply Beads” makes visible from the first roll: the two operations look different on the string, feel different in the hands, and produce structurally different results.
What researchers like Jo Boaler independently observed about children developing more robust mathematical thinking through flexible exploration rather than rigid procedures confirms what Split the Array makes possible from the beginning: there is always more than one way to decompose a rectangle, and the child who finds both understands something the child who follows one procedure does not.
What cognitive scientists studying embodied understanding independently observed — that abstract mathematical concepts are grounded in physical experience — confirms what TALK DO WRITE makes structurally explicit: the gesture of n-folding is not a stepping stone to the symbol. It is the same mathematical idea expressed in a different semiotic register, simultaneously.
Boaler, J. (2016). Mathematical mindsets: Unleashing students’ potential through creative math, inspiring messages and innovative teaching. Jossey-Bass.
Cobb, P., Yackel, E., & Wood, T. (1992). A constructivist alternative to the representational view of mind in mathematics education. Journal for Research in Mathematics Education, 23(1), 2–33.
Devlin, K. (2000). The math gene: How mathematical thinking evolved and why numbers are like gossip. Basic Books.
Dienes, Z. P. (1971). Building up mathematics (4th ed.). Hutchinson Educational.
Fosnot, C. T., & Dolk, M. (2001). Young mathematicians at work: Constructing multiplication and division. Heinemann.
Lakoff, G., & Núñez, R. E. (2000). Where mathematics comes from: How the embodied mind brings mathematics into being. Basic Books.
Verschaffel, L., Greer, B., & De Corte, E. (2007). Whole number concepts and operations. In F. K. Lester (Ed.), Second handbook of research on mathematics teaching and learning (pp. 557–628). Information Age.
Multiplicative Reasoning: From Operations to Expression
Use the Linear Abacus® to explore when to multiply versus add, and how to break down larger multiplications using the distributive property.
Games at a Glance- 100 Add or Multiply Beads — Roll a digit, then choose: add it, or multiply it by 10 (n-fold it). Race to reach 100 without going over.
- Split the Array — Build a multiplication on the string, then split the rectangle into two smaller rectangles to make the calculation manageable.
- Multiplicative thinking — Reasoning about equal groups and their total, structurally distinct from adding.
- Distributive property — Breaking down multiplication: a × (b + c) = (a × b) + (a × c), visible as two rectangles on the string.
- n-folding — Creating n-sized groups and repeating them a specific number of times.
- Decomposition — Breaking numbers into parts to make calculation easier, always verifiable on the beads.
“Why did you choose this operation?” · “How can you split this multiplication to make it easier?” · “Can you explain your strategy in your own words?”
Ready to Play?
Use this blog alongside the Games Book for the full set of probing questions, illustrated student reasoning, and diagrams that bring each game to life.
The Games Book contains thirty games, complete instructions, probing questions, student reasoning examples, and diagrams — everything you need to sit down and play with confidence.