PERCENT GRID
Percentages Math Game
Learn that percent means "rate per 100" by shading squares on a 10x10 grid. Convert fractions to percentages, match target percents, and solve real-world rate-per-100 problems. Aligned with Lesson 24 Percent and Rates per 100 (Eureka Math Grade 6, Module 1).
How to Play
- 1Read the target percentage or fraction displayed at the top of the screen.
- 2Click or drag across the 10x10 grid to shade the matching number of squares.
- 3Remember: percent means "per 100," so 45% means shading 45 out of 100 squares.
- 4For fractions, convert to an equivalent fraction with 100 as the denominator first.
- 5Submit your answer when the correct proportion of the grid is shaded.
- 6Progress through levels that introduce decimals, mixed numbers, and word problems.
Rules
- The 10x10 grid always contains exactly 100 squares.
- Each shaded square represents 1% (one per hundred).
- Targets may be given as percentages (45%), fractions (9/20), or decimals (0.45).
- You must shade the exact number of squares. Over-shading or under-shading counts as incorrect.
- Click a shaded square again to un-shade it if you make a mistake.
- Later levels include word problems where you must determine the percentage before shading.
Top Tips!
“The key to mastering percent and rates per 100 is to think of the denominator first. For any fraction, ask: "How do I turn this denominator into 100?" If the target is 3/5, multiply both numerator and denominator by 20 to get 60/100, meaning 60 squares. For 7/25, multiply by 4 to get 28/100, so shade 28 squares. For decimals, move the decimal point two places right: 0.72 becomes 72 squares. Once you internalise that percent literally means "per hundred," every conversion becomes a single multiplication step.”
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Representing a Percentage on the Grid
Shade 35% on the 10x10 grid.
- 135% means 35 per 100.
- 2The grid has exactly 100 squares.
- 3Count and shade 35 squares (3 full rows of 10 = 30, plus 5 more).
- 4Check: 35 shaded squares out of 100 total = 35/100 = 35%.
35 squares shaded. Because percent means "per 100," the number of squares to shade always equals the percentage value directly.
Converting a Fraction to a Percent (Lesson 24 Method)
What percent is 3/4? Show it on the grid.
- 1To convert 3/4 to a rate per 100, find an equivalent fraction with denominator 100.
- 2Ask: 4 times what equals 100? Answer: 25.
- 3Multiply both parts: 3 x 25 = 75, 4 x 25 = 100.
- 4So 3/4 = 75/100 = 75%.
- 5Shade 75 squares on the grid (7 full rows + 5 extra).
3/4 = 75%. The grid visually confirms that three-quarters of 100 squares is 75 squares. This is the core method taught in Lesson 24: express any rate as a rate per 100.
Converting a Decimal to a Percent
Express 0.08 as a percent and show it on the grid.
- 1Move the decimal point two places to the right: 0.08 becomes 8.
- 20.08 = 8/100 = 8%.
- 3Shade 8 squares on the grid (less than one full row).
- 4Check: 8 out of 100 = 0.08 = 8%.
0.08 = 8%. Small percentages like this are easy to visualise on the grid because you can see how few squares are shaded compared to the whole.
Solving a Rate-per-100 Word Problem
A survey found that 17 out of 50 students prefer maths. What percent is that?
- 1The rate is 17 out of 50. To express this per 100, double both numbers.
- 217 x 2 = 34, 50 x 2 = 100.
- 3So 17/50 = 34/100 = 34%.
- 4Shade 34 squares on the grid to verify.
34% of students prefer maths. The "rate per 100" approach from Lesson 24 works for any real-world ratio: find the equivalent fraction with 100 as the denominator.
What is Percent and Rates per 100? (Lesson 24 Explained)
The word "percent" comes from the Latin "per centum," which literally translates to "per hundred" or "for every hundred." When we say 45%, we mean 45 out of every 100. This is the foundational concept taught in Lesson 24 of Eureka Math Grade 6 Module 1, and it is the key insight that makes all percentage calculations possible.
A rate per 100 is simply a way of expressing any ratio using 100 as the reference point. Instead of saying "17 out of 50 students passed," we convert to a rate per 100: "34 out of 100 students passed," or 34%. This standardisation makes it easy to compare rates that originally had different denominators. Is 17/50 bigger or smaller than 23/75? Converting both to rates per 100 (34% vs approximately 31%) answers the question instantly.
The 10x10 grid model used in Percent Grid makes this concept tangible. Because the grid contains exactly 100 squares, each square represents exactly 1%. Shading 45 squares means 45%. Shading 7 squares means 7%. There is no abstraction needed. Students can see and count the percentage directly.
How to Convert Any Fraction to a Percent Using the Rate-per-100 Method
The method taught in Lesson 24 for converting fractions to percentages is elegant in its simplicity: find an equivalent fraction with 100 as the denominator. For example, to convert 3/5 to a percent, ask "5 times what equals 100?" The answer is 20. Multiply both numerator and denominator by 20: 3/5 = 60/100 = 60%.
This method works cleanly for fractions whose denominators are factors of 100 (2, 4, 5, 10, 20, 25, 50). For other denominators, students learn to divide the numerator by the denominator and multiply by 100. For example, 2/7 = 2 divided by 7 = 0.2857, times 100 = approximately 28.6%.
The Percent Grid game reinforces both approaches. Students start with "friendly" fractions (1/2, 1/4, 3/5) where the denominator divides evenly into 100, then progress to more challenging fractions where estimation and rounding become necessary. This progression mirrors the scaffolding approach recommended in Eureka Math Lesson 24.
Why the 10x10 Grid Model is the Best Way to Learn Percentages
Research in mathematics education consistently shows that visual models produce deeper understanding than abstract formulas alone. The 10x10 grid is particularly effective for teaching percentages because it eliminates the need for any mental conversion. The grid IS 100. Each cell IS 1%. The visual directly represents the mathematical concept.
This concrete-to-abstract progression follows the proven CPA (Concrete, Pictorial, Abstract) approach used in Singapore Math and recommended by mathematics educators worldwide. Students who build their percentage understanding on the grid model develop stronger proportional reasoning skills that transfer to more advanced topics like probability, statistics, and financial mathematics.
The Percent Grid game adds interactivity to this proven model. Instead of passively looking at a pre-shaded diagram, students actively shade squares, make mistakes, self-correct, and build genuine ownership of the concept. This active engagement produces significantly better retention than passive observation, which is why interactive tools consistently outperform static worksheets in educational research.
Real-World Applications of Rates per 100
Once students understand that percent means "per 100," they can interpret percentages everywhere in daily life. Sale discounts (30% off means paying 70 out of every 100 cents), battery levels (78% means 78 out of 100 units of charge), weather forecasts (60% chance of rain means roughly 60 out of 100 similar days would have rain), and test scores (85% means 85 correct out of every 100 questions) all become immediately intuitive.
The rate-per-100 framework also connects directly to more advanced concepts in later grades. Interest rates (5% annual return means $5 earned per $100 invested), tax rates (20% income tax means $20 paid per $100 earned), and statistical data (voter turnout of 62% means 62 out of every 100 eligible voters participated) all rely on the same foundational understanding.
By building this understanding through the visual grid model in Grade 6, students develop the conceptual foundation that supports percentage-based reasoning throughout secondary school and into adult financial literacy. The rate-per-100 mental model is one of the most practically useful concepts in all of mathematics education.
Learning Objective
Understand that percent means "per 100" and develop fluency in converting fractions, decimals, and ratios into percentages using the 10x10 grid model, as outlined in Lesson 24 of Eureka Math Grade 6.
Best For
- Ages 10 to 12 (Grade 5-6: introduction to percent as rate per 100)
- Ages 12 to 14 (Grade 7-8: reinforcement and complex conversions)
- Ages 14+ (review and exam preparation)
- Adults (foundational percent understanding for financial literacy)
Curriculum Relevance
- Directly aligned with Eureka Math Grade 6 Module 1 Lesson 24: Percent and Rates per 100
- Supports Common Core 6.RP.A.3c: find a percent of a quantity as a rate per 100
- Reinforces 6.RP.A.3: use ratio and rate reasoning to solve real-world problems
- Supports UK KS2/KS3 percentage objectives in the National Curriculum
- Recommended as visual scaffolding before abstract percentage calculations
Teachers
The perfect companion for Lesson 24
Percent Grid is designed as a direct interactive supplement to Eureka Math Grade 6 Module 1 Lesson 24. Use it as a warm-up activity before the lesson, as guided practice during the lesson, or as independent follow-up work. The visual grid model reinforces the "rate per 100" concept in a way that worksheets alone cannot. Every student can work at their own pace through progressively harder challenges.
Parents
Help your child understand what percent really means
Many children memorise percentage formulas without understanding what percent actually means. This game builds genuine comprehension by letting them see that 45% is literally 45 out of 100 squares. If your child is working through Eureka Math Lesson 24 or any percentage unit, this visual practice reinforces the lesson in a hands-on way that sticks.
Students
See percentages instead of just calculating them
Forget memorising rules. With the Percent Grid, you can actually see what 75% looks like, what 12% looks like, and why 1/4 equals 25%. Once you understand that "percent" just means "out of 100," every percentage problem becomes straightforward. Use the grid to check your homework answers or to build confidence before a test.