These games review the place value concept of 100 more and 100 less, and 10 more and 10 less for the numbers 100-900. On a turn players cover a clue and the answer. While they play, they attempt to make the longest line of counters in their color. As they play, students mentally add 10 or 100 to a given number 100-900, and mentally subtract 10 or 100 from a given number 100-900.WHAT YOU NEED TO KNOWThere are 4 game boards in this collection. 2 games review 100 more or less and 10 more or less.2