The purpose of this quantitative correlational study was to determine if and to what extent statistically significant correlations exist between high school STEM teachers' attitudes toward the use of computer technology and the duration of software utilization in their classrooms in the United States. This research was based on the Unified Theory of Acceptance and Use of Technology (UTAUT). The study was conducted during the COVID-19 pandemic with a nationwide convenience sample of 144 high school STEM teachers. The online survey was hosted on SurveySwap (2024). The questionnaire included demographic and professional questions and the validated Computer Attitudes Scale. The results of nonparametric Spearman's rho correlation analysis, evaluated at corrected [alpha] = 0.01, indicated a statistically significant positive correlation between high school STEM teachers' confidence in using technology and the duration of software utilization in their classrooms ([rho] = 0.216, p = 0.009). The other results indicated positive but statistically nonsignificant relationships of duration of software utilization with teachers' overall attitude ([rho] = 0.192, p = 0.021), perceived computer usefulness ([rho] = 0.191, p = 0.022), computer liking ([rho] = 0.126, p = 0.134), and computer anxiety ([rho] = 0.206, p = 0.013). These findings provided insights for educational policy and professional development programs to enhance classroom technology use. [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.]