Since 2013, she has served as the Deputy Superintendent for the Monterey County Office of Education. Prior to coming to the county office, Deneen served as:
- District superintendent of Soledad Unified School District
- Associate superintendent of educational services
- Director of curriculum and instruction
- Principal and assistant principal
- Classroom teacher for 10 years, including teaching
in a bilingual program for two years - Master teacher for teacher candidates
- Mentor teacher for new teachers
- Former college adjunct professor for San Jose State University