Honolulu firefighters were called to Kamiloiki in east Oahu after four students and two staff members got sick from a strong chemical odor.  It was noticed at about 9 a.m. and the school investigated, but could not determine the source.  They reported it to firefighters, who did an extensive survey, with the  hazardous materials crew. Children were still experiencing nausea, dizziness and headache, so the school implemented its evacuation plan.  The students were evacuated at about 11 a.m. to Kaiser High School and their parents were called. Firefighters could not determine the source of the odor.  It's the second time in two days that students were sickened by an odor.  Yesterday, eight students and two adults at Pohakea and Kaimiloa Elementary schools were treated when they got sick after a neighbor sprayed the pesticide malithion.