Depression is a risk factor for suicide in adolescents making it essential for school nurses to identify and refer at-risk adolescents for resources. At the project site, there is no current practice to routinely assess for adolescent depression. The purpose of this quantitative, quasi-experimental quality improvement project was to determine if implementation of the Lighthouse Project's Columbia-Suicide Severity Rating Scale (C-SSRS) screening tool would impact the rate of identification and referrals to a psychologist or social worker among at-risk adolescents age 12-17 years old. The project took place in a school district in Southern California over four weeks. Watson's theory of caring and Prochaska and DiClemente's stages of change model were the theoretical underpinnings of the project. Data on depression identification was obtained from the use of the C-SSRS tool and referrals from the AERIES Student Information System. The total sample size was N = 1239 students, n = 1230 in the comparative group and n = 9 in the implementation group. A chi-square test showed no statistically significant improvement in identification of depression with X[superscript 2] (1, N = 1239) = 1.12238E-67, p = 2.673. Although no statistical significance was found, clinical significance increased from 5% pre to 100% post-intervention. The C-SSRS tool provided needed areas for reinforcement of depression assessment and increased nursing staff awareness. Recommendations include repeating the project when all adolescents are back in school attendance from COVID-19 is over and there is a larger sample size over a longer period of time. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]