I love games that ask students to problem solve using several different skill sets at once. In this game of Decimal Darts, students are asked to visualize, estimate, and use logical reasoning. Balloons are placed at random intervals along a number line marked by random beginning and ending numbers. Students then need to enter a number that they believe represents the location of a balloon along the number line. A dart is thrown to pop the balloon. Students then move on to the next balloon or re-adjust their answers if the dart missed. The challenging aspect of this game is that the balloons are not placed at predictable fixed intervals, and the beginning and ending points are also varied.
Decimal Darts makes a great whole class competition. Divide your class in half and use two player mode to have students compete to pop the most balloons. Be sure to alternate which team begins each game since seeing one dart thrown creates a significant advantage.
Decimal Darts would also make an excellent center activity for an upper elementary unit on estimation. Partners could use two player mode to compete or one player mode to complete the activity together by discussing and justifying their estimates.
Note: If using Decimal Darts on an interactive whiteboard, you may want to use the Zoom feature in your browser to enlarge the game for better viewing.