The attributes that students observe in their teachers may affect their learning. This study investigated the science and math high school teachers’ profile and characteristics and their students’ achievements in the subjects using descriptive comparative and correlational designs. Fifty-six teachers and 2240 students from 13 Religious of the Virgin Mary (RVM) high schools in regions XI and XII in Southern Mindanao were randomly selected as subjects. Majority of the teachers were profiled as female, 25 years old or younger, with less than five years teaching experience and rare attendance or speakerships in national and international seminars; bachelor’s degree graduates, many with honors, of accredited HEIs; and licensed by the Professional Regulations Commission (PRC). Overall, they manifest outstanding and very satisfactory levels of professional and personal qualities, respectively. The students’ mean scores in science achievement test are satisfactory and comparable for both regions; while very satisfactory and satisfactory for region XI and XII, respectively in mathematics, exhibiting significant difference (t = 3.91, p < .05). Pearson r test revealed significant relationships between teacher professional and personal qualities with students’ science and math achievements (p values < 0.05), implying that students’ achievements are functions of teachers’ characteristics.