Based on previous studies in Second Language Acquisition (SLA), this book provides new information and pioneering research for academicians, educational technicians, language test developers, psychologists and second language researchers. It examines the cases of learning and testing in languages other than English (as a second language, L2), specifically focusing on the Portuguese case. This book also reinterprets the immigrants’ populations and their schooling (and concepts) considering the recent immigration changes. It encourages research in L2 research, focusing on other minorities and European contexts, including the refugees’ argument that is affecting/reinforcing European society. It reflects on the expected cognitive processing difference according to the mother tongues of children and their cognitive map structures. The author selects literature concerning the disproportions among L2 learners and the commonly saturated focus on English as a L2. This book is essentially evidence-based, providing specific data and statistical analyses to understand the size of disproportions showed by the professional perceptions and the risk of underrepresented minorities that could be misled inside host schools in Europe.