The first day of classes for North Wasco County School District 21 is still about a month away, but those who need to get new students registered should do so now.  D-21 Superintendent Candy Armstrong says offices at all schools are open to do that and answer questions, and the district website also has registration information.  School starts on September 5 for elementary schools and sixth and ninth graders, with the rest beginning the next day.  Armstrong notes classes at Wahtonka Community School, which operates on a year-round schedule, began last month.