In addition, King's aggressive upbreeding led to tremendous improvements in equine stock. The King Ranch had upbreeding programs for both thoroughbreds and quarter horses. For example, Assault, the 1946 winner of the Triple Crown, was the result of the King Ranch's breeding programs. More widely known and recognized are the quarter horses on the King Ranch. Visitors to the Ranch can observe some of the best examples of quarter horses that exist today, and they can also learn about Wimpy and Mr. San Peppy, two of the early quarter horses that helped establish the superiority of King Ranch equines. Even more importantly, visitors to the ranch can watch modern cowboys work these quarter horses in the same way as their ancestors, and learn, first-hand, what makes a quarter horse a champion. Students should be asked to observe and report on five characteristics of quarter horses that make them ideally suited for ranch work.

Domestic stock forms only a portion of the animals on the ranch. One of the lessons that students can learn at the ranch is about wildlife. The ranch features an impressive array of wildlife, which can be observed by visitors to the ranch. These animals include bobcats, deer, coyotes, quail, turkey, and wild hogs. Students can learn about innovations that the King Ranch pioneered to help protect wildlife, including providing water to wildlife, providing shelter for quail and other wildlife, and promoting the growth of plant species necessary to sustain wildlife. In addition, an industrious teacher may be able to get students to speak with the scientists involved in two ongoing wildlife research projects, the South Texas Quail Project and the South Texas Buck Capture Project. If those scientists are unavailable, a teacher may be able to get his students involved in one of the King Ranch's ongoing projects, which are mainly game surveys. The ranch also provides students with the unique opportunity to learn about and possibly observe several endangered or threatened species, including the Texas indigo snake, aplomado falcon, Harris' hawk, and the ferruginous pygmy-owl.

Wildlife management is only one aspect of the environmental stewardship that students can learn upon visiting the ranch. One of the most important lessons one can learn at the ranch is that farmers and ranchers have an obligation to look after the land. Students can view the best practices used on the ranch, which are aimed at limiting the impact of the ranching on the land. These practices include soil conservation, minimum-impact grazing programs, water conservation, and the limited and controlled use of pesticides. Students can learn about and explain why each of these programs helps the environment.