.:Abstract:.

Did galaxies in the early universe produce stars at the same rate as galaxies today?  What environmental factors affect the star formation rate of galaxies? Data at 24-micron wavelengths for three intermediate-redshift galaxy clusters were taken with the Spitzer Space Telescope were acquired to derive the star formation rates (SFR) of the cluster galaxies. Imaging data from the Hubble Space Telescope and the ESO Distant Cluster Survey (EDisCS) were used. The clusters differed in mass, degree of relaxation, and number of members. Physical properties such as morphology, VRIJK magnitudes, local density, and presence of merging galaxies were analyzed in order to correlate how factors in the internal and external environment of clusters affect SFR.  The cluster galaxies were also compared to field galaxies. The SFRs of the clusters were compared to other redshift studies to provide a more complete picture of how the SFR of galaxies has changed over time. The SFRs of all galaxies correlate to their morphologies, color, and being merging galaxies. Also, galaxies within clusters tended to have lower SFRs overall compared to those in the field. Galaxy harassment and ram-pressure stripping played a role in the difference between cluster and field galaxy SFR. When comparing the SFRs of clusters at 3 different redshifts, there is a large increase in SFR at intermediate redshifts.