Despite the multiplicity of research available related to best teaching practices and learning strategies for students learning languages, most of it focuses on English-speaking students learning a foreign language and on non-English speakers learning English. In contrast, studies on using best instructional practices and learning strategies towards the education of heritage Spanish-speakers and students who had prior Spanish knowledge studying Spanish in a class with a curriculum designed for beginner, non-Spanish speakers are very limited or non-existent. The purpose of this research is to determine the effect of utilizing best teaching practices and differentiation approaches developed for addressing the literacy needs of students based on the findings in my literature review and applying those strategies in my intervention in order to address the specific literacy needs of both Spanish heritage speakers and more advanced students enrolled in my Spanish 2 class. This action research project revealed that there was a significant increase in the achievement scores of experimental group students in the activities designed according to differentiation approach developed within the scope of this study. The effectiveness of the intervention used in this study should be informed to all teachers across the country faced with addressing the literacy needs of students in an academically heterogeneous demographic group about how they will guide the process of preparing and incorporating effective teaching practices and implementing differentiation methods.