Gas-phase nitrogen oxides are important in the formation of tropospheric ozone. NO[subscript x] (NO and NO[subscript 2]) as well as tropospheric ozone have been shown to have negative effects on human health. Therefore, accurately measuring NO[subscript x] concentrations in the atmosphere is important. In this laboratory experience, students measured ambient NO[subscript x] concentrations using a relatively simple and inexpensive passive sampling/UV-vis spectroscopy technique. The students used two different types of spectrophotometers to determine limits of detection and ambient NO[subscript x] concentrations. Data demonstrated both spectrometers behaved similarly, proving laboratories utilizing different spectrophotometers could accurately perform the experiment. Although not statistically verified due to the limited number of passive samplers employed in the pilot experiment, measured NO[subscript x] concentrations were similar to those calculated by a local air quality model (within approximately 50 parts per billion). At the end of the laboratory experience, students compared their measured NO[subscript 2] concentrations to the United States Environmental Protection Agency's primary and secondary standard of 53 parts per billion (annual mean). The initial learning goals of the experiment included the following: the successful creation of calibration curves, the determination of spectrophotometer limit of detection, and the calculation of ambient NO[subscript x] concentrations. The experiment is appropriate for students enrolled in analytical and environmental chemistry courses.