Carolyn’s outline of combining classes describes well how many (especially smaller) schools create a manageable schedule of classes. The creation of “grade levels” has a somewhat arbitrary history and makes most sense in large “graded” schools. (What “grade level” is Little House in the Big Woods?) Thinking in terms of several levels (lower/upper elementary) is helpful when combining classes. Planning for instruction of students separated by a year or more in age in a class is very similar to planning instruction for those of different skill levels in the same year’s age group.