This study compared job stress levels of Texas agricultural science cooperating teachers and Texas agricultural science student teachers across a semester. The research objectives included describing secondary agricultural science cooperating teachers and student teachers perceptions of stressors, by time of semester (beginning, middle, and end), describing perceptions of frequency of stressors, by time of semester (early semester, mid semester, and late semester) among secondary agricultural science cooperating teachers and student teachers, and determining if differences existed between agricultural science student teachers' and cooperating teachers' based on perceptions of job stress and time of semester (early semester, mid semester, and late semester). Job stress severity declined among student teachers as the semester progressed and increased in cooperating teachers at the midpoint of the semester, but then declined toward the end of the semester. Job stress frequency increased in student teachers throughout the semester and declined in cooperating teachers at mid-semester with a slight increase at the end of the semester. Job pressure index scores showed similar trends with an increase throughout the student teaching semester.