Hispanics have become the largest minority in the United States. One in five public school students are Hispanic and more than two third of them are English Language Learners (ELL). While most Hispanic ELL students are born in the United States (2nd generation) and tend to be concentrated in elementary schools, ELL foreign born students (1st generation) tend to be concentrated more at the upper grades. This has put great pressure on high schools to educate these students that do not know English and still have to understand and learn academic content in order to graduate from high school. This book provides a descriptive analysis of the possible association between heritage language maintenance and academic achievement. By continuing the development of their first language, ELL students may be able to transfer cognitive linguistic abilities to the acquisition of academic English. This study may provide insights to professionals in the field of Second Language Acquisition and Public Policy in Education on how to better serve immigrant students so they can do well in school.