A fluorometer is a device that measures the spectroscopic properties of fluorescent materials, and fluorometry is used widely in chemistry research settings to characterize fluorescent samples. One of the obstacles faced by undergraduate programs looking to implement fluorometer-based experiments into their laboratory curriculum is the high cost of these instruments. We have designed a low-cost fluorometer that is suitable for teaching principles of fluorescence spectroscopy, and in this work, we provide instructions for the assembly and testing of this device. This home-built instrument, which we call the Fluorino, is constructed from inexpensive 3D printable optomechanical components, an Arduino Uno microcontroller, and low-cost optical and electronic components, and it is controlled by open-source software. Once assembled, the Fluorino can be used by students to measure and record fluorescence emission intensities in steady state as well as changes in fluorescence emission intensities in real time. This work represents an effort to expand accessibility to fluorescence spectroscopy education by providing a low-cost alternative to commercial instruments.