Currently, the American educational establishment promotes the traditional idea that the causes of truancy rest with truants themselves. The general tendency in educational administration is to regard school as an unchallengeable good such that any child willfully absenting himself from it must be rebellious and/or deficient. While this thinking may describe some truants, certain recent research, including this dissertation suggests to the contrary that most truants are students who snake rational choices as to whether to attend school or to attend certain classes after they have arrived in school. The present dissertation belongs to a relatively new tradition, with two main novel features. First, to the idea of School Truancy there has been added the notion of Class Truancy. The research cohort of which this dissertation is a part, has shown that, in the western state where our research was based, though School Truancy is common, Class Truancy is even more common. Secondly, this new tradition proposes that truancy is most fruitfully explored when it is seen as a rational response to inadequacies in curriculum and pedagogy. The particular focus of this dissertation is the tendency for ethnic minorities in high schools to truant from school and class. My findings show that if our large student sample is at all typical, there is massive truancy in American high schools and a disproportionately large truancy by ethnic minorities. This tendency to higher than average truancy by ethnic minorities is understandable, since there is a fast growing number of immigrants who flow into the United States each year. The largest of these minority groups is Hispanic. Unfortunately, relatively little truancy research has been done with this group or, for that matter, any other minority group. The thesis has sought to uncover the relationship between students belonging to ethnic minorities, including those for whom English is a second language, and their truancy. A survey was administered to 2727 high school students in the western United States, and 962 students in the eastern United States. The survey questions were constructed to gain information regarding the students' demographic profiles, truancy patterns both from school and class over the previous two months, students' attitudes toward school regarding value of education, reading, parents, friends, teachers, and English as a second language. This study found serious truanting taking place in these schools among both Caucasian and ethnic minority students, with higher levels among the ethnic minorities. We also found high truancy levels among those students who speak English as a second language, mainly from those who perceive their English proficiency in understanding, speaking, reading and writing to be weak. The findings suggest that the percentage of high school students who truant is shockingly high. They also suggest that the causes of truancy may lie more in curriculum and pedagogical arrangements than in deficiencies in the truants themselves. This suggested cause would seem to demand that administrators and teacher educators elevate the truancy problem to a much higher priority than it seems to enjoy now. My thesis makes certain recommendations as to how the problem may be better understood so that effective solutions may be found.