Summary

In this activity, groups of students will play a game to review and practice explaining key terms related to gases and gas laws. One at a time, students will attempt to get their teammates to say the designated term, while trying to avoid saying any of the prohibited words during the explanations.

Grade Level

High School

Objectives

By the end of this activity, students should be able to:

• Explain key terms in a way that goes beyond basic memorized definitions.

Chemistry Topics

This activity supports students’ understanding of:

• Gases
• Gas Laws
• Ideal Gas
• Measurements

Time

Teacher Preparation: 20-30 minutes to prepare the re-usable sets

Lesson: 15-30 minutes

Materials

• Don’t Say It! card set (1 needed for each group of 4 students)
• 1-2 timing devices per group (optional)

Safety

• There are no particular safety precautions for this activity.

Teacher Notes

• This activity was created as part of the Chemistry Fun section of the March 2026 issue of Chemistry Solutions.

• It is best to print the card sets on cardstock. Teachers should cut on the dotted lines only.
• This activity can be used as a quick review game to:
  • summarize after the unit
  • review for an assessment or after returning from a break
  • determine students’ readiness for an assessment
  • review 1^st-year chemistry topics before teaching an AP Chemistry unit on gases
• There are 27 terms. Each term includes a list of 4 associated words or short phrases that are not allowed to be used when one partner is attempting to get another to say the term.
  • The “Don’t Say It!” words were chosen specifically in attempt to press students toward more conceptual explanations, rather than relying on memorized facts.
• The rules of game play are found at the end of these notes and contain general rules for students to follow. The rules can be projected for the entire class or photocopied and distributed to students individually.
• Suggested game play:
  • One set of cards is placed in a pile for each group of four students. Within the group of four, students break into teams of two to compete against each other to earn the most points.
  • Example: A and B compete against X and Y
    • Something silly like Rock, Paper, Scissors can be used to determine which team will go first. (In this example, team A/B goes first and decides that A will be the “explainer” and B will be the “guesser”.)
    • A draws a card from the pile, then silently reads it and shows it to X and Y.
    • A uses descriptions and attempts to explain concepts to prompt B to say the term that is on the card. X and Y monitor to make sure that A doesn’t accidentally or intentionally use any of the forbidden, “don’t say it” words that are listed on the card.
      • If B correctly guesses the term, team A/B earns a point, and the turn ends.
      • If the term is not guessed, or if A uses a forbidden word, then team X/Y earns a point, and the turn ends.
    • When the turn ends, play moves to the other team. Team X/Y decides who will be the explainer and the guesser for their first turn. The explainer draws a card, shows it to A and B, and proceeds in the same way as the first turn.
• Flow of the game: The explainer and guesser for each team must switch roles for each turn, so all students will play the roles of explainer and guesser multiple times.
• Possible game variations using time restrictions:
  • Assign a time limit (recommendation is 20-40 seconds) for each turn.
    • If the card is not guessed AND no forbidden words are used within the time limit, then the explainer can set the card aside to try again after all other cards are played. If it is not correctly guessed after a 2^nd try, it should be set aside, and no team earns the point.
  • Instead of alternating teams and players, each team can be given the same number of cards and will attempt to earn the point for each card in a rapid-fire round. The winner is the team with the lowest time.
    • For groups of 4 in teams of 2, set aside 3 cards, to be used in case of a tie, and divide the remaining 24 between the two teams. Each team then divides the cards evenly between players, so each student will hold 6 cards. Choose the team to go first:
      • A and B should sit facing each other.
      • X and Y stand behind A to monitor the forbidden, “don’t say it” words.
        • X is the timer for the entire round.
        • Y is the timer for the “passed” cards (explained below)
      • A is the explainer, while B is the guesser, until all 6 cards are either earned (correctly guessed) or sacrificed (lost due to the use of a prohibited word).
      • B becomes the explainer as soon as all cards from A have been played.
      • The round is over when all 12 cards have either been played or sacrificed.
    • Rules and points:
      • A team can “pass” on any card and come back to it but cannot skip any. Once any passed cards come back into the rotation the card is sacrificed if not correctly guessed within 2 minutes. Sacrificed cards do not count for either team.
      • The team score is their “correct-guess-rate”,  .

The Rules

• Be careful! Players must avoid saying any of the words listed after “Don’t say…” on each card.
• In addition, you may not use any of the following as you try to get your teammate to say the designated words:
  • Physical gestures
  • Symbols in place of words (like P for pressure)
  • “Sounds like…”