The purpose of this research is to identify teaching strategies and practices that impact the vocabulary and language development for English Language Learners. Today, there are over 3.5 million non-English speaking students enrolled in public classrooms and the number has continued to climb over the past decade. Many ELL students live in poverty and attend underfunded schools that are generally staffed by under-qualified teachers. Facing low academic achievement, the ELL students' test scores are invariably lower than their English speaking peers and consequently, many of them drop out of high school before they have a chance to become productive citizens. This qualitative research was conducted at three urban public elementary schools located in the southeastern part of the United States. Through in-depth interviews and observations with seven teachers of ELL students, this study provides information of the strategies and practices that impact vocabulary and language proficiency levels. The findings and conclusions consist of the following: (a) teachers must use strategies that are based upon language development and have been proven to work with ELL students, (b) teachers must use Sheltered Instruction Observation Protocol (SIOP) strategies and practices in order that lesson content is made comprehensible and understandable and (c) pre-service education programs and staff development for teachers must prepare teachers to work with our culturally and linguistically diverse students. This research adds to the body of academia knowledge regarding specific strategies and teaching models that will enhance learning and improve academic achievement for ELL students. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]