This document summarizes an experimental study on the use of fly ash to partially replace cement and glass aggregate to partially replace fine aggregate in concrete mixes. Concrete cubes were made with 0%, 10%, 20%, and 30% replacements of cement by fly ash and 0%, 10%, 20%, and 30% replacements of fine aggregate by glass aggregate. The cubes were tested for compressive strength at 3, 7, and 28 days. The results showed that compressive strength generally increased with 10-20% replacements, but decreased with 30% replacements. The highest 28-day compressive strengths were 43.26 MPa with 20% cement replacement and 20% fine aggregate replacement, and 43.73 MPa with 10% cement replacement and 20