This document discusses a project using HOBO data loggers to record lighting usage in classrooms at Cal State Long Beach in order to identify rooms with malfunctioning occupancy sensors. The HOBO meters record when lights are on and off, with one meter able to collect data over days or months. The project involves placing HOBO meters in classrooms for at least a week to obtain usage data, then analyzing the data to find rooms where lights stay on when unoccupied. This helps the university identify areas for energy savings through repairs or adjustments to occupancy sensors. Results found annual savings of 34,500 kWh, $4,500, and reductions in CO2 emissions.