Objective: The aim of this study was to develop a decision support system that helps school nurses manage health problems they encounter while caring for the elementary and secondary school students, and evaluate usability of it.

Methods: Knowledge was aquired by literatures review and interviews with senior school nurses and was validated by another group of school nurses. The Omaha System was used as a standardized nursing terminology to describe nursing diagnoses and interventions. The system was developed under the Windows environment. C++ was used as a program language and MS Structured Query Language as a database. To investigate usability of the system, 30 school nurses in elementary and secondary schools were recruited and asked to apply it to nursing problems they encountered in actual students care setting.

Results: The decision support system with seven major signs and symptoms was developed. It automatically makes a nursing diagnosis based on the input data, and also provides nursing interventions with evidence. It was proven that the system was very useful for school nurses to manage students' health problems.

Conclusion: The system will contribute to development of expert knowledge concerning student's health problems and improve the quality of school nursing and professionalism.