Ratings of perceived exertion have been shown to be a valid method of monitoring physical activity intensity for both adults and children. As such, this subjective method may serve as an alternative to objective measurements for assessing students' performance on national standards 2 and 4. The OMNI-Child perceived exertion scales were developed with mode-specific pictorial descriptors and child-friendly verbal descriptors to help children measure their perceived exertion during physical activity. These ratings are simple, low-cost alternative objective technologies like heart rate monitors, pedometers, and accelerometers. Furthermore, an understanding of the relationship between perceived exertion and exercise intensity can provide students with a monitoring tool that can be used both inside and outside of the classroom.