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Offline Classroom Activities — Mathematics 5

Term 1 · Week 7 · Multiplying a Fraction by a Fraction · CG Quarter 1, competency 8

Five activities: three individual, two group. Every one of them runs with no electricity, no devices and no printing budget. Where a printed sheet would help, an equivalent board-and-paper route is given beside it.

Activity Time Grouping Best used
I-1 The Fold Book 20 min Individual Day 1 — replaces the digital game
I-2 Grid Cards 25 min Individual Day 2–3 — the model and the rule
I-3 The Product Hunt 25 min Individual Day 4 — extension
G-1 The Product Wall 35 min Groups of 5 Day 4 — consolidation
G-2 Cooking for the Fiesta 40 min Teams of 5–6 Day 5 — application

Preparing the paper (once, reused all week)

The only consumable this week is rectangular scrap. Any of these work:

About 8 pieces per learner covers the whole week. They do not need to be the same size as each other, and saying so out loud is worth thirty seconds: "Your whole and my whole are different sizes, and half of each is still a half." That single remark heads off the most common Grade 5 fraction error — comparing fractions of different wholes.

Pre-creasing thirds and fifths the night before saves five minutes a day and is worth doing for any class where fine-motor difficulty is present.


INDIVIDUAL ACTIVITIES

I-1 · The Fold Book

Time 20 minutes · Grouping Individual · Use Day 1, replaces the digital game

A learner leaves this activity holding physical proof that ½ × ½ = ¼. That object is the point; the recording sheet is secondary.

Materials

Preparation

None. Tear the paper in front of the class.

Instructions

  1. Fold, shade, count each of the five pairs below, one per scrap.
  2. On each scrap, write the two fractions in the top corner before folding.
  3. After opening, write the count in the bottom corner: pieces altogether and pieces with both marks.
  4. Stack the five scraps in order and staple or tie them — that is the fold book.
  5. On the recording quarter-sheet, copy the five results into the table.
Fold this Then this Pieces altogether Both marks Product Simplest form
1 ½ ½ 4 1 1/4 ¼
2 ½ 6 1 1/6
3 ½ 6 2 2/6
4 ¾ ½ 8 3 3/8
5 ¾ 12 6 6/12 ½

(Teacher's copy. Learners receive columns 1–3 only.)

  1. At the bottom of the recording sheet, answer in one sentence: "Was every product smaller than both the fractions you started with?"

The question to ask while circulating

Only one, and ask it of every learner:

"Is your answer smaller than both the fractions you started with?"

A learner who has counted correctly but cannot answer this has produced numbers without meaning. Note the name — that is the Day 2 small group.

Differentiation

Group Adjustment
Below level Rows 1–3 only, done carefully, with pre-creased scraps
On level All five
Above level All five, then: "Make a sixth page where the product is exactly ⅒." (⅕ × ½, or ½ × ⅕)
Additional needs Pre-folded scraps; the recording sheet may be dictated to a peer scribe

Assessment — 10 points

Criterion Points
Five folds completed and stacked 2
Counts correct on all five (1 point each, ½ point if only one column is right) 5
Products written in simplest form 2
Closing sentence answered, with any reasoning 1

Written Works.


I-2 · Grid Cards

Time 25 minutes · Grouping Individual · Use Day 2–3, the model and the rule

Folding cannot reach ⅗ × ¾. This activity is where the learner discovers that for themselves and reaches for a grid instead.

Materials

Preparation

If drawing grids by hand will eat the lesson, draw one grid on the board of each size needed (3 × 4, 4 × 5, 5 × 6, 6 × 8) and have learners copy the one they need. Copying a grid is not the competency.

Instructions

For each product: decide the grid size, draw it, shade across, shade down, count.

The rule for deciding — which learners should state before drawing:

Columns = the denominator of the first fraction. Rows = the denominator of the second.

Product Grid needed Shaded cells Total cells Answer Simplest form
1 ⅔ × ¾ 3 × 4 6 12 6/12 ½
2 ⅗ × ¾ 5 × 4 9 20 9/20 9/20
3 ⅖ × ⅚ 5 × 6 10 30 10/30
4 ⅜ × ⅔ 8 × 3 6 24 6/24 ¼
5 ⅞ × ½ 8 × 2 7 16 7/16 7/16
6 ¾ × ⅘ 4 × 5 12 20 12/20
7 ⅚ × ⅗ 6 × 5 15 30 15/30 ½
8 ⅗ × ½ 5 × 2 3 10 3/10 3/10

(Teacher's copy. Learners receive column 2 only.)

The moment this activity is designed to produce

After item 3 or 4, a learner will notice they can get the shaded count without drawing — 2 × 5 = 10, 5 × 6 = 30. When that happens, do not confirm it. Say:

"Try it on the next one and check it against the drawing. If it works three times in a row, come and tell the class."

That learner then delivers Day 3's rule, which is worth far more than hearing it from you.

Differentiation

Group Adjustment
Below level Items 1, 5 and 8 only — the smallest grids. Grids pre-drawn
On level Items 1–6
Above level All eight, then: "Item 7 gives ½. So does item 1. Find a third pair that gives ½ and prove it without drawing."
Additional needs Enlarged pre-drawn grids; shading may be marked with an X in each cell rather than filled

Assessment — 10 points

Criterion Points
Grid size chosen correctly (½ point each, 8 items) 4
Counts and products correct (½ point each) 4
Simplest form given where reduction is possible (items 1, 3, 4, 6, 7) 2

Written Works.


I-3 · The Product Hunt

Time 25 minutes · Grouping Individual · Use Day 4, extension

Every other activity this week runs forwards: two fractions in, one product out. This one runs backwards, which is harder, open-ended, and the fastest way to tell a secure learner from a fluent one.

Materials

Instructions

The answer is given. Find the question — as many times as you can.

For each target below, find pairs of fractions whose product is exactly that target. Both fractions must be proper (smaller than 1), and no denominator may be larger than 10. Write each pair and show the multiplication that proves it.

Target Find at least
¼ 3 pairs
3 pairs
½ 2 pairs
3 pairs

Answer key

Not exhaustive — accept any pair that multiplies correctly and obeys the two rules.

Target Valid pairs (denominators ≤ 10, both proper) Check
¼ ½ × ½ 1/4
¾ × ⅓ 3/12 = ¼
⅔ × ⅜ 6/24 = ¼
⅖ × ⅝ 10/40 = ¼
⅚ × 3/10 15/60 = ¼
⅞ × 2/7 14/56 = ¼
½ × ⅔ 2/6 = ⅓
¾ × 4/9 12/36 = ⅓
⅗ × 5/9 15/45 = ⅓
⅖ × ⅚ 10/30 = ⅓
½ ⅔ × ¾ 6/12 = ½
⅗ × ⅚ 15/30 = ½
⅘ × ⅝ 20/40 = ½
⅞ × 4/7 28/56 = ½
½ × ⅓ 1/6
⅔ × ¼ 2/12 = ⅙
⅚ × ⅕ 5/30 = ⅙
¾ × 2/9 6/36 = ⅙
⅜ × 4/9 12/72 = ⅙

The strategy worth surfacing at the end

Ask the class how they found their pairs. Two methods will emerge, and both are worth naming:

  1. Guess and check — multiply pairs until one lands. Slow, but it works.
  2. Build from the target — ¼ is 1/4, and 1/4 = (1 × 1)/(2 × 2), or (1 × 3)/(3 × 4), or (2 × 3)/(3 × 8). Take any fraction equivalent to the target and split its numerator and denominator between two fractions.

Method 2 is genuinely a Grade 8 factoring idea arriving early. A learner who finds it should be asked to explain it, slowly, to the class.

Assessment

Not scored out of a fixed total — the task is open. Record against three bands:

Band Evidence
Extending Met every target, found a systematic method, can explain it
Secure Met every target by guess and check, all products verified correctly
Developing Met some targets; products correct where found

Performance Tasks, if you use it as a graded piece. Most teachers will not — its value is diagnostic.


GROUP / TEAM ACTIVITIES

Both activities assume a crowded room with fixed desks. Neither requires learners to move furniture, and each names what to do when the class is 45 or more.


G-1 · The Product Wall

Time 35 minutes · Groups of 5 · Use Day 4, consolidation

The class builds one large reference chart, in pieces, that stays on the wall for the rest of the term.

Materials

Preparation

Write the group assignments on the board before the class comes in. Each group gets one first fraction and produces its whole row.

Group First fraction Products to build
1 ½ ½×½, ½×⅓, ½×¼, ½×⅕
2 ⅓×½, ⅓×⅓, ⅓×¼, ⅓×⅕
3 ¼ ¼×½, ¼×⅓, ¼×¼, ¼×⅕
4 ⅔×½, ⅔×⅓, ⅔×¼, ⅔×⅕
5 ¾ ¾×½, ¾×⅓, ¾×¼, ¾×⅕
6 ⅗×½, ⅗×⅓, ⅗×¼, ⅗×⅕

Roles — assign one to each member, do not let them volunteer

Role Responsibility
Grid-drawer Draws the four grids, correctly sized. Draws nothing else
Shader Shades across and down. May not write numbers
Counter Counts cells and states the fraction aloud. May not shade
Recorder Writes the product and the simplest form under each grid
Checker Verifies every product by the rule — numerator × numerator — independently, and signs the sheet

The split between Shader and Counter is deliberate: it forces the count to be spoken, which is where errors surface.

Instructions

  1. 5 min — roles assigned, sheet ruled into four boxes.
  2. 20 min — build the four models and record the products.
  3. 5 min — Checker verifies all four by the rule and signs. Any disagreement is resolved by recounting the grid, not by arguing.
  4. 5 min — sheets taped to the wall in order, Reporters read their row aloud.

Answer key

× ½ × ⅓ × ¼ × ⅕
½ ¼
1/12 1/15
¼ 1/12 1/16 1/20
2/9 2/15
¾ ¼ 3/16 3/20
3/10 3/20 3/25

What to point out once the wall is up

Two things, and they are worth five minutes:

Managing 45+ learners at fixed desks

Run seven or eight groups rather than six by adding and rows. Nobody moves: the group is whoever is within arm's reach. Pass the large sheet along the row rather than gathering around it.

Differentiation

Group Adjustment
Below level Assign row ½ or ¼ — unit fractions, smallest grids
Above level Assign row , and ask the group to predict the ⅘ row without drawing it
Additional needs The Counter role is fully verbal; the Checker role can be done with a calculator

Assessment — group rubric, 12 points

Criterion 3 2 1
Accuracy All four products correct and in simplest form 3 correct 2 or fewer
Model quality Grids correctly sized, shading legible from the back of the room Correct but untidy Grid size wrong
Roles Every member did their own role only Roles blurred once or twice One or two members did everything
Verification Checker verified independently and caught or confirmed each Checker signed without visible working No verification

Performance Tasks.


G-2 · Cooking for the Fiesta

Time 40 minutes · Teams of 5–6 · Use Day 5, application

The week's arithmetic, inside a problem the learners recognise. This is the activity that teaches "of" means multiply better than any exercise set, because the word appears naturally.

Materials

Preparation — 5 minutes

Write the recipe on the board:

BIKO — serves 12

  3/4  kilo glutinous rice
  1/2  kilo brown sugar
  2/3  litre coconut milk
  1/4  kilo grated coconut
  1/2  teaspoon salt

Roles

Role Responsibility
Reader Reads each line aloud and states what operation is needed. May not compute
Computer A Works the first three ingredients
Computer B Works the last two ingredients
Checker Recomputes every answer independently. Signs each line
Reporter Presents to the class and answers one question from another team
Timekeeper (6th member) Calls the halfway point and the two-minute warning

Instructions

Part 1 — 12 min. Half the recipe. The fiesta committee needs enough for 6 people. Every quantity must be halved. Write each as a multiplication.

Part 2 — 12 min. Two-thirds of the recipe. A different committee needs enough for 8 people — that is ⅔ of 12. Every quantity multiplied by ⅔.

Part 3 — 8 min. The question that matters. Answer in writing, as a team:

"For Part 1 you multiplied by ½. Every answer got smaller. Is there any quantity you could multiply this recipe by that would make the answers bigger? Give one, and explain."

Part 4 — 8 min. Reporters present Part 3. Take three teams, not all of them.

Answer key

Part 1 — × ½ (serves 6)

Ingredient Working Answer
Glutinous rice ½ × ¾ ⅜ kilo
Brown sugar ½ × ½ ¼ kilo
Coconut milk ½ × ⅔ ⅓ litre
Grated coconut ½ × ¼ ⅛ kilo
Salt ½ × ½ ¼ teaspoon

Part 2 — × ⅔ (serves 8)

Ingredient Working Answer
Glutinous rice ⅔ × ¾ ½ kilo
Brown sugar ⅔ × ½ ⅓ kilo
Coconut milk ⅔ × ⅔ 4/9 litre
Grated coconut ⅔ × ¼ ⅙ kilo
Salt ⅔ × ½ ⅓ teaspoon

Part 3. Any multiplier greater than 1. Expected answers: "double it — multiply by 2, for 24 people"; "one and a half times, for 18". Accept 3/2, 2, 2½, or "×2". The reasoning required is that the multiplier is more than one whole, not the specific number.

The trap in Part 2, and it catches most teams. ⅔ × ¾ = 6/12 = ½ kilo, which is more than the ⅜ kilo of Part 1. Teams that have absorbed "multiplying makes it smaller" too literally will assume they have erred. They have not — ⅔ is a bigger multiplier than ½, so a bigger answer follows. If no team raises it, raise it yourself in Part 4. It is the sharpest available demonstration that the week's sentence is about size relative to one, not about multiplication in general.

Managing 45+ learners at fixed desks

Teams are rows. The Reader stands; nobody else moves. If there are more than eight teams, run Part 4 with four reporters and have the rest submit Part 3 in writing.

Differentiation

Group Adjustment
Below level Part 1 only, with the multiplication written out for the first line as a model
On level Parts 1–3
Above level Add Part 2b — "scale it for 18 people" (× 3/2), which requires an improper multiplier
Language support The Reader role may be performed in the mother tongue; the written record is in English
Additional needs Computer roles may use fraction strips; the Reporter may present from written notes

Assessment — group rubric, 12 points

Criterion 3 2 1
Part 1 accuracy All five correct and simplified 3–4 correct 2 or fewer
Part 2 accuracy All five correct and simplified 3–4 correct 2 or fewer
Reasoning in Part 3 Correct, with a clear explanation of why a multiplier over 1 increases the amount Correct multiplier, thin explanation Incorrect or absent
Roles and verification Every role performed; Checker signed each line Roles blurred, or checking partial One or two members did everything

Performance Tasks.


Which activity to reach for

If your class… Run
Has no devices at all I-1 on Day 1, I-2 on Day 2 — together they replace the game entirely
Is split on the Day 1 exit ticket I-2 with pre-drawn grids for the lower half, I-3 for the upper
Finished early and is restless I-3. It has no ceiling
Needs the term performance-task mark G-1 or G-2 — both are rubric-scored and both are defensible as Performance Tasks
Has one 40-minute slot and nothing prepared G-2. The only preparation is writing five lines on the board

Part of the E-turo MATATAG artifact set. Companion files: lesson-plan.md · lesson-plan-ilaw.md · syllabus.md · assessment.md · slides.html · game.html · worksheet.html