Plenty in 20

Plenty of number practice in 20 questions, from Year 1 to GCSE.

A Plenty in 20 page showing a grid of 20 number questions

How Plenty in 20 works

Each level gives 20 quick questions on the number skills that matter most for one year group. Click once for a fresh set, reveal the answers, or open any question to see the full working.

Use it on the board, or print it as a one-page worksheet with answers.

The levels are named after gemstones rather than year groups, so you can choose the right level for any class or child without anyone knowing which year it is aimed at.

Primary Years 1 to 6

Six levels, from counting within 20 to fractions, percentages and ratio.

Quartz

Year 1

  • Count forwards and backwards within 20
  • One more and one less
  • Number bonds within 10 and to 10
  • Add and subtract within 10
  • Count in 2s, 5s and 10s
  • Tens and ones in teen numbers
All 20 skills
  1. Count forwards within 20
  2. Count backwards within 20
  3. One more than a number
  4. One less than a number
  5. Write numbers in figures
  6. Number bonds within 10
  7. Number bonds to 10
  8. Add two single-digit numbers
  9. Subtract within 10
  10. Double numbers to 10
  11. Count in 2s
  12. Count in 5s
  13. Count in 10s
  14. Compare numbers
  15. Order numbers
  16. Place value: tens and ones
  17. Partition teen numbers
  18. Missing numbers on a number line
  19. Add 10 to a single digit
  20. Subtract ones from teen numbers
Open Quartz

Opal

Year 2

  • Number bonds to 20
  • Add and subtract 2-digit numbers
  • 2, 5 and 10 times tables
  • Divide by 2 and by 10
  • Halves and quarters of amounts
  • Place value to 100
All 20 skills
  1. Number bonds to 20
  2. Place value to 100
  3. Compare and order numbers to 100
  4. Write numbers in figures
  5. Count in 3s
  6. Add two 2-digit numbers (no regrouping)
  7. Add two 2-digit numbers (with regrouping)
  8. Subtract 2-digit numbers (no regrouping)
  9. Subtract 2-digit numbers (with regrouping)
  10. 2 times table
  11. 5 times table
  12. 10 times table
  13. Divide by 2
  14. Divide by 10
  15. Half of numbers to 40
  16. Quarter of numbers to 40
  17. Double 2-digit numbers
  18. Fractions of shapes
  19. Find 1/2 of a quantity
  20. Find 1/4 of a quantity
Open Opal

Amber

Year 3

  • Number bonds to 100
  • Add and subtract 3-digit numbers
  • 3, 4 and 8 times tables
  • Multiply 2-digit by 1-digit
  • Round to the nearest 10 and 100
  • Fractions: add, subtract, equivalent, of an amount
All 20 skills
  1. Number bonds to 100
  2. Write numbers in figures
  3. Add 3-digit and 2-digit numbers
  4. Add two 3-digit numbers
  5. Subtract 2-digit from 3-digit numbers
  6. Place value in 3-digit numbers
  7. Compare 3-digit numbers
  8. Round to the nearest 10
  9. Round to the nearest 100
  10. 3 times table
  11. 4 times table
  12. 8 times table
  13. Add fractions (same denominator)
  14. Subtract fractions (same denominator)
  15. Equivalent fractions
  16. Unit fraction of an amount
  17. Non-unit fraction of an amount
  18. Multiply 2-digit by 1-digit
  19. Count in 50s
  20. Count in 100s
Open Amber

Jade

Year 4

  • 6, 7, 9, 11 and 12 times tables
  • Factor pairs
  • Add and subtract fractions; equivalent fractions
  • Decimal tenths
  • Recognise negative numbers
  • Multiply and divide by 10 and 100

Plus the four written methods, place value and rounding

All 20 skills
  1. Written addition
  2. Written subtraction
  3. Written multiplication
  4. Written division
  5. Place value
  6. Rounding
  7. 6 times table
  8. 7 times table
  9. 9 times table
  10. 11 times table
  11. 12 times table
  12. Factor pairs
  13. Add fractions (same denominator)
  14. Subtract fractions (same denominator)
  15. Equivalent fractions
  16. Decimal tenths
  17. Write numbers in figures
  18. Recognise negative numbers
  19. Multiply by 10 and 100
  20. Divide by 10 and 100
Open Jade

Topaz

Year 5

  • Add and subtract fractions with different denominators
  • Mixed numbers and improper fractions
  • Add and subtract decimals
  • Percentages of amounts
  • Square, cube and prime numbers
  • Order of operations

Plus the four written methods, place value and rounding

All 20 skills
  1. Written addition
  2. Written subtraction
  3. Written multiplication
  4. Written division
  5. Place value
  6. Rounding
  7. Add fractions (different denominators)
  8. Subtract fractions (different denominators)
  9. Multiply fractions by integers
  10. Improper fractions to mixed numbers
  11. Mixed numbers to improper fractions
  12. Add decimals (2 dp)
  13. Subtract decimals (2 dp)
  14. Multiply and divide decimals by 10, 100, 1000
  15. Percentage of amounts
  16. Square numbers
  17. Cube numbers
  18. Prime numbers to 100
  19. Factors and multiples
  20. Order of operations
Open Topaz

Ruby

Year 6

  • Multiply fractions; divide fractions by integers
  • Add and subtract mixed numbers
  • Percentages of amounts; one number as a percentage of another
  • Add and subtract negative numbers
  • Simplify and share ratios
  • HCF, LCM and order of operations

Plus the four written methods, place value and rounding

All 20 skills
  1. Written addition
  2. Written subtraction
  3. Written multiplication
  4. Written division
  5. Place value
  6. Rounding
  7. Multiply fractions
  8. Divide fractions by integers
  9. Add and subtract mixed numbers
  10. Percentage of amounts
  11. One number as a percentage of another
  12. Add negative numbers
  13. Simplify ratios
  14. Share in a ratio
  15. Subtract negative numbers
  16. Order fractions, decimals and percentages
  17. Order of operations (with brackets)
  18. HCF of two numbers
  19. LCM of two numbers
  20. Write numbers in figures
Open Ruby

Key Stage 3 Years 7 to 9

Three levels that secure and extend number skills before GCSE.

Sapphire

Year 7

  • Negative numbers: all four operations
  • Convert and order fractions, decimals and percentages
  • Fractions: all four operations
  • Percentage increase and decrease
  • Factors, multiples and primes
  • Simplify and share in ratios

Plus the four written methods, place value and rounding

All 20 skills
  1. Written addition
  2. Written subtraction
  3. Written multiplication
  4. Written division
  5. Place value
  6. Rounding
  7. Add and subtract negative numbers
  8. Multiply and divide negative numbers
  9. Order negative numbers
  10. Convert between fractions, decimals and percentages
  11. Order fractions, decimals and percentages
  12. Equivalent fractions and simplifying
  13. Add and subtract fractions (different denominators)
  14. Multiply and divide fractions
  15. Percentage of amounts
  16. Percentage increase and decrease
  17. Square and cube numbers
  18. Factors, multiples and primes
  19. Simplify and share in ratios
  20. Order of operations
Open Sapphire

Emerald

Year 8

  • Multiply and divide decimals
  • Fractions and mixed numbers: all four operations
  • Percentage change; express as a percentage
  • Three-part ratios
  • Direct and inverse proportion
  • Powers and metric units

Plus the four written methods, place value and rounding

All 20 skills
  1. Written addition
  2. Written subtraction
  3. Written multiplication
  4. Written division
  5. Place value
  6. Rounding
  7. Multiply decimals
  8. Divide decimals
  9. Add and subtract mixed numbers
  10. Multiply fractions
  11. Divide fractions
  12. Percentage of amounts
  13. Express as a percentage
  14. Percentage change
  15. Three-part ratios
  16. Direct proportion
  17. Inverse proportion
  18. Calculate with powers
  19. Order of operations
  20. Metric units
Open Emerald

Pearl

Year 9

  • Round to decimal places and significant figures
  • Estimation
  • Complex fraction calculations
  • Percentage change and multipliers
  • Direct proportion and ratio problems
  • Convert fractions, decimals and percentages

Plus the four written methods and ordering integers

All 20 skills
  1. Written addition
  2. Written subtraction
  3. Written multiplication
  4. Written division
  5. Order integers
  6. Rounding
  7. Round to decimal places
  8. Round to significant figures
  9. Estimation
  10. Multiply by powers of 10
  11. Complex fraction calculations
  12. Percentage change
  13. Fraction of an amount
  14. Negative number operations
  15. Percentage multipliers
  16. Direct proportion
  17. Multiply decimals
  18. Ratio problems
  19. Convert fractions, decimals and percentages
  20. Order of operations
Open Pearl

GCSE Years 10 and 11

A Foundation and a Higher level for each year. Higher levels assume the Foundation skills.

Amethyst

Year 10 · Foundation

  • Standard form: write and convert
  • Percentage increase and decrease
  • Add and subtract fractions and decimals
  • Share in a ratio
  • Convert and order fractions, decimals and percentages
  • Estimation and best buys

Plus the four written methods, ordering and rounding

All 20 skills
  1. Written addition
  2. Written subtraction
  3. Written multiplication
  4. Written division
  5. Order integers
  6. Rounding
  7. Standard form (large numbers)
  8. Standard form (small numbers)
  9. Convert from standard form
  10. Percentage of amounts
  11. Percentage increase and decrease
  12. Add and subtract fractions
  13. Add and subtract decimals
  14. Squares and cubes
  15. Share in a ratio
  16. Convert fractions, decimals and percentages
  17. Order fractions, decimals and percentages
  18. Estimation
  19. Best buys
  20. Multiply by powers of 10
Open Amethyst

Onyx

Year 10 · Higher

  • Standard form calculations
  • Index laws, including negative, zero and fractional indices
  • Compound percentage change, growth and depreciation
  • Reverse percentages
  • Fractions to recurring decimals
  • Simplify surds

Plus the four written methods, place value and rounding

All 20 skills
  1. Written addition
  2. Written subtraction
  3. Written multiplication
  4. Written division
  5. Place value (standard form)
  6. Rounding
  7. Standard form (multiply and divide)
  8. Standard form (add and subtract)
  9. Index laws (multiply)
  10. Index laws (divide)
  11. Index laws (power of a power)
  12. Negative and zero indices
  13. Fractional indices
  14. Compound percentage change
  15. Compound growth and depreciation
  16. Fraction arithmetic
  17. Reverse percentages
  18. Fractions to recurring decimals
  19. Divide a line segment in a ratio
  20. Simplify surds
Open Onyx

Garnet

Year 11 · Foundation

  • Standard form calculations
  • Compound percentage change and multipliers
  • Ratio, inverse proportion and exchange rates
  • Speed, distance, time
  • Negative numbers; multiply and divide fractions
  • Midpoints

Plus the four written methods, place value and rounding

All 20 skills
  1. Written addition
  2. Written subtraction
  3. Written multiplication
  4. Written division
  5. Place value (standard form)
  6. Round to significant figures
  7. Standard form calculations
  8. Index laws (positive)
  9. Compound percentage change
  10. Operations with negative numbers
  11. Inverse proportion (workers)
  12. Exchange rates
  13. Share in a ratio
  14. Speed, distance, time
  15. Round to decimal places
  16. Percentage multipliers
  17. Convert between fractions, decimals and percentages
  18. Fraction of an amount
  19. Find the midpoint
  20. Multiply and divide fractions
Open Garnet

Diamond

Year 11 · Higher

  • Surds: add, subtract, multiply, divide
  • Rationalise denominators
  • Negative and fractional indices; index laws
  • Upper and lower bounds; error intervals
  • Direct and inverse proportion
  • Recurring decimals to fractions

Plus the four written methods, place value and rounding

All 20 skills
  1. Written addition
  2. Written subtraction
  3. Written multiplication
  4. Written division
  5. Place value (standard form)
  6. Round to significant figures
  7. Round to decimal places
  8. Multiply and divide surds
  9. Add and subtract surds
  10. Rationalise denominators
  11. Fractional indices
  12. Negative indices
  13. Index laws (all types)
  14. Upper and lower bounds
  15. Error intervals
  16. Multiply and divide decimals
  17. Direct proportion
  18. Inverse proportion (squared)
  19. Recurring decimals to fractions
  20. Standard form (negative powers)
Open Diamond