Games & Simulations

Monster Line


In Monster Line, various monsters are attacking a city. Their goal is to reach and destroy the tall building—its location on the number line denoted by a number at the bottom of the screen. In each round, the player fires one or more pie launchers at the monsters. Each pie launcher has an integer (its location on the number line) and an operation associated with it. The player can supply either a positive or negative integer for each pie launcher, with the intent that the resulting sum, difference, product, or quotient will equal the location of one of the monsters on the number line.

Every round, the monster moves a certain number of spaces along the number line. Each monster moves a different number of spaces, so some of them will advance more quickly toward the target building. Monsters can also destroy pie launchers if they are allowed to advance along the number line to the location of the launcher.

It may require more than one pie to defeat a monster, so depending on the number of pie launchers and monsters in the level, the student may need to go through multiple rounds. Pie launchers with either division or multiplication operators may not be able to be used in every round, but pies launched by these operators will destroy a monster in one hit, so they are more powerful than the subtraction and addition pie launchers, which require three pies to destroy a monster.

Teacher Notebook

The research reported here was supported by the Institute of Education Sciences, U.S. Department of Education, through Grant R305C080015 to the National Center for Research on Evaluation, Standards, and Student Testing (CRESST).