Doubles and halves within 100 and 1000 review games / activities for 3rd and 4th Grade (and more able 2nd and review in 5th): review doubling and halving 2 and 3 digit numbers / big numbers. Fun multiplication math centers, stations, rotations, early finisher activities, fast finisher extension challenge activities, doubling and halving large numbers group tasks, bell ringers, morning work, warm ups, fun math fillers, or extra practice activities. Printable PDF. 10 Four in a Row boards3x30-card