The COVID-19 pandemic, changing demographics, student diversity, and increased accountability compel educators to challenge uniform constraints of traditional instruction and create an environment focused on individual achievement. Differentiated instruction empowers teachers to target multiple learning styles through varied themes, adapted content delivery, and assessment options. This quantitative quasi-experimental research study examined the effects of differentiated instruction on seventh grade student performance on standardized mathematics assessments using a repeated-measures design. Two independent research trials, controlling for initial group differences, provided inconclusive assessment results however, several implications for classroom practice can be gleaned from the findings.