Resources and Tools for Elementary Math Specialists and Teachers
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Deep Sea Duel

This iOS app for the Illuminations online card game Deep Sea Duel (cataloged separately) helps users develop mental computation skills by finding sums of 3 or 4 numbers. A student and the opponent, Okta the octopus take turns selecting cards. The first one to reach the target sum with 3 cards (in the 9-card game) or 4 cards (in the 16-card game) wins the game. You can choose how many cards are presented (9 or 16), what types of numbers they display (small integers through tricky decimals), and Okta's level of strategy. The game is not timed but depends on strategic planning in order to defend against Okta's moves while trying to collect a winning group of cards.
Contributed by: National Council of Teachers of Mathematics, Publisher
Math TopicNumber Sense, Decimals, Basic Operations, Mathematical Practices, Mathematical Processes
Grade Level2, 3, 4, 5, 6+
Resource TypeActivity, Game, Mobile App

  • Additional Information
    • AudienceLearner
    • LanguageEnglish (USA), Chinese, Dutch, French, German, Italian, Spanish
    • Education Topic
    • Interdisciplinary Connection
    • Professional DevelopmentNo
    • ContributorNational Council of Teachers of Mathematics, Publisher
    • Publication Date2012-08-02
    • RightsCopyright (c) 2012 National Council Teachers of Mathematics
    • AccessFree access
  • Standards
    • Common Core State Standards for Mathematics

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