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Find the Match: Prefixes Game

Collage with Metric images including: Scale, measuring tape, nutrition label, voltage meter, tube, sign
Credit: NIST
Keywords:International System of Units, SI, metric system, unit, prefix, measurement, team, individual, game, play, collaboration, activity, classroom, STEM, education, meter, kilogram, ampere, kelvin, mole, candela, second, length, mass, electric current, thermodynamic temperature, amount of substance, luminous intensity, time
Audience:Student, parent, educator, general public, academic coordinator, outreach ambassadors, formal, informal
Grade Level:3 to Higher Education
Subjects:STEM, mathematics, physical science, chemistry, biology and life sciences, earth science, engineering, environmental science, physics


Multiplayer (max 4) or single
Difficulty Level:

Easy to moderate


50 minutes (adjust as needed)


SI Units Card Game-NIST Interns enjoy playing SI Units Card Game Find the Match - Prefixes-2023
NIST interns enjoy playing the SI Units Card Game “Find the Match – Prefixes.”
Credit: NIST

This card game is published in the SI Units Card Deck (SP 1297) and is designed to build familiarity with the International System of Units (SI, commonly known as the metric system) while applying memory skills. With its simple rules and engaging objectives, this educational game offers an enjoyable opportunity for students to successfully apply the SI prefixes. Familiarity with the SI prefixes will prepare students to successfully make measurements in science, technology, engineering, and mathematics (STEM) applications.

The SI prefixes are used to form decimal multiples and submultiples of units. They allow very large or very small numerical values to be avoided. Currently, 24 prefixes are recognized for use, ranging from 1030 to 10−30. A prefix name attaches directly to a unit name. A prefix symbol attaches directly to the unit symbol. A prefix is inseparable from the unit name or symbol to which it is attached. For example, millimeter (mm) or meganewton (MN).


  • One complete set of the SI prefixes decks sets H and I (large and small). Prepare the necessary decks by downloading the SI Units Card Deck (SP 1297) digital file (PDF) according to the instructions. Assemble the necessary companion resources and instructions.
  • SI Prefixes chart (Resource 5).

Learning Objective:

The primary objective of the game is to uncover and match the cards in the set. In each round, match the corresponding SI prefixes name/symbol cards to the factor cards.

  • DEMONSTRATE relationships between the SI prefixes.
  • APPLY strategic decision-making during gameplay.
  • COLLABORATE and COMMUNICATE within a team.

Game Tips:

It is crucial to pay close attention to every turn in the game. Remembering the location of cards is required to form a pair.

Game Modifications:

The number of cards revealed can be increased or decreased to vary the difficulty level of each round. For a cooperative variant, players work in pairs to determine matches.


Picture showing metric cards laid out on brown table top
Arrange cards face down.
Credit: NIST

Shuffle one SI prefixes set, either large or small (set H or I) and arrange cards face down in rows and columns.

  • Round 1: set H (large name/symbol and factor).
  • Round 2: set I (small name/symbol and factor).
  • Round 3: combine sets H and I (large and small).




SI Units Card Game-NIST Interns enjoy playing SI Units Card Game Find the Match - Prefixes-2023
During the game, players turn over cards and consult the SI Prefixes chart to verify each pair.
Credit: NIST
  1. The players take turns flipping over either 6 cards (easy level) or 4 cards (moderate level) from the table, meaning 3 or 2 white cards AND 3 or 2 black cards.
    • If these cards DO form a valid pair the player collects the pair and earns and additional turn.
    • If these cards DO NOT form a valid pair, they must be flipped back down in the original position, and it becomes the next player’s turn.
    • Participants may validate a correct pair by using the SI Prefixes chart (Resource 5).
  2. Players continue taking turns until all the cards have been successfully paired.


Determining the Winner:

Once all the pairs have been correctly matched, players tally the number of cards collected throughout the game. The player or team with the highest number of cards emerges as the champion.

Classroom Connections



Created December 5, 2023, Updated June 27, 2024