Number Codes is a great activity that incorporate elementary coding with using the number grid in math class. Students follow coding symbols that represent 10 more, 10 less, 1 more, and 1 less to find the mystery number. Students also have the opportunity to create own number codes that lead to a mystery number. This activity makes for a great whole group activity or math center. Number grid and answer key included. Number Codes supports the Common Core Standards of Mathematics and the New Jersey Student Learning Standards.