This invention pertains to a system for continuous observation of rodents in home-cage environments with the specific aim to facilitate the quantification of activity levels and behavioral patterns for mice housed in a commercial ventilated cage rack. The home-cage in-rack provides daytime and nighttime monitoring with the stability and consistency of a home cage environment. The system is made up of a dual-video camera hardware design mounted on a video rack and an executable software means for automatic detection and processing for tracking multiple animals. The National Cancer Institute’s Radiation Biology Branch seeks partners interested in licensing or collaborative research to co-develop a video monitoring system for laboratory animals.