Three Gram-negative bacteria and one Gram-positive bacterium were isolated from environmental samples in an undergraduate microbiology class on the basis of antibiotic resistance. Isolate DNA was purified, sequenced, and assembled using a hybrid approach. Here, we report the genomes of Acinetobacter johnsonii CSUSB1, Aeromonas hydrophila CSUSB2, Bacillus velezensis CSUSB3, and Comamonas thiooxydans CSUSB4.