Licensed practical nurses (LPNs) are health care workers who take care of people who are sick, injured, or unable to care for themselves. They work with the direction of a physician or registered nurse. All LPNs in the United States must pass a licensing examination called the NCLEX-PN which can only be taken after completing a state-approved practical nursing program. A high school diploma is required for enrollment. In the next 8 years, employment of LPNs is expected to grow 14 percent.