This mixed method study examined the possible influence of a military deployment online tutorial on teacher knowledge. DoDEA and public school teachers were the two groups used for the study. From this exploratory study, the researcher also wanted to explore if teachers would find professional development provided in an online tutorial relevant and useful for expanding their knowledge of military children. Empirical studies of online professional development opportunities for teachers in the area of military children and deployment appear meager. Similarly, there are few empirical studies that evaluate teacher knowledge concerning military deployments. The tutorial was used to inform these teachers of three important areas related to deployment and military children: (1) how deployment is defined and what the deployment cycle entails, (2) stressors children encounter as a result of having a parent deployed and (3) what teachers can do to help children with deployment stressors encountered during deployment. The findings revealed that there was a statistically significant difference (p less than 0.01) in overall teacher knowledge. The researcher wanted to know the relationship of teachers' overall knowledge of deployment related issues as measured by the pretest, the online tutorial, and the posttest measure of deployment knowledge. The results provided evidence of a statistically significant improvement in teacher knowledge after participating in the online Military Deployment Tutorial. The large effect size provided strength and confidence in the validity of the instrument. Comments from the survey portions of the instrument revealed that the online military tutorial is beneficial as a public service to educate participants and raise awareness of military deployments. Implications for school administrators and recommendations for future studies were addressed in chapter five. This research study was not only prompted by the literature surrounding the topic, but also by the realities witnessed by the researcher as a child, throughout his time in military service, and as a DoDEA teacher. [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://www.proquest.com/en-US/products/dissertations/individuals.shtml.]