Another weather-related two-hour delay greeted North Wasco County School District 21 students as they returned from winter break Tuesday, the fourth such delay to go along with three full day closures forced by icy weather in the last month.  That means adjustments to the school calendar are coming.  D-21 Superintendent Candy Armstrong says to get the required number of classroom hours in, they will at least be adjusting the schedule for the second trimester.  Before the winter break, Hood River County School District Superintendent Dan Goldman said his district expected to add school days at the end of the year to make up for two full day cancellations and four two-hour delays.  A snow make-up day is in the Hood River County school calendar during late January, and the rest will probably be made up later in the year.  The Hood River district also had a two-hour delay Tuesday.