If you are planning a college visit to Cal Poly SLO then you have come to the right page. Learn more about Cal Poly SLO, a large public university based in San Luis Obispo, California. There are about 20,400 undergraduate students enrolled at the university and 1,000 graduate students. The school mascot is Musty the Mustang and the school colors are green and gold. One fun fact about the school…the popular smoothie chain, Jamba Juice was created by students at the school as a senior project.