Reading is one of the most important skills that students learn in elementary school. The problem addressed in this study is the decrease in proficiency of reading comprehension when primary grade students are assessed using a digital device to read and respond to instead of reading a text from a paper-based test. The purpose of this study is to determine how teachers perceive their primary grade students' (students in grade kindergarten, one, two or three) reading comprehension is affected by the modality, (paper versus screen) in which they read a text. The theoretical framework that guided the study is the cognitive load theory. A qualitative case study was used for the study as this allowed for an in-depth investigation of teachers' perceptions and experiences surrounding the use of either paper texts, or digital texts in the elementary classroom. Data was collected for a period of 13 weeks from 10 participants. Participants answered survey questions using an online survey and then participated in a one-on-one Zoom interview. The data shows that teachers perceive their primary grade students comprehend better when reading text from paper. Knowing that students are assessed yearly by using digital devices, poses a need for students to have some degree of exposure to reading from digital devices. This leads to the need for more education on the use of digital devices in the classroom. Future research recommendations would be to do a similar qualitative case study with a larger, and more diverse group of participants. Another recommendation is to conduct a quantitative case study using actual data from student assessments in reading comprehension. [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.]