A group of nursing students from University of Nevada, Reno spent Friday teaching fourth-graders at Fremont Elementary School how to avoid getting sick this season. They said it's very easy to do, "Specifically, hand washing."School nurse Sheila Bridges invited the group, saying every year at this time the number of colds, flu cases and other illnesses rise in the school.Jennifer Hinnant said studies have shown simple handwashing and following a few other common sense rules can reduce student absences by a third in just five weeks.Those precautions, according to nursing professor Bernie Longo, are designed to "break the chain of …