1.无(熟练程度)等级的
2.〈美〉(教育)不分班级的
1.describes an elementary school that is not pided into classes
2.not sorted into different sizes
1.The Nongraded Teaching in American Elementary Schools
美国小学教育中非年级化教学
2.The Commentary on the Nongraded Education
美国不分年级教育述评