Mathematical knowledge and skills are crucial to success in academics and the workplace. The Common Core State Standards emphasizes fraction teaching and learning in elementary school. This mixed-method study explores fraction concept understanding among 14 deaf and hard of hearing participants between the ages of 8 and 16, as quantitatively measured by their ability to describe the properties of fractional numbers, convert between fractional numbers and their visual representations, and determine the order and equivalence of fractional numbers. Furthermore, the qualitative study was supplemented by interviews with the deaf participants and surveys with their parents and teachers to examine use of mathematical fraction concepts in the student participant's experience, at home and in the classroom. Results indicated a strong understanding of fractional magnitude/size when comparing two fractions; however, putting several fractions in order from the smallest to the largest was a struggle for the participants. The findings also support the call for increased incidental learning opportunities between deaf and hard of hearing children and their parents along with increased use of practical applications of fractional numbers, and additional training for teachers who teach fractions to deaf students.