Executive Summary Claire Lilienthal Elementary School (CLS) strives to provide an excellent education for children in the San Francisco Unified School District. Over 690 children are studying in the school, and their background is very diverse, the largest group of the students (30%) being of Asian descent. Apart from the comprehensive curriculum, CLS provides additional opportunities, and the full day Korean-English Immersion program (KIP) is one of them. Nowadays, bilingualism can be regarded as a typical environment for children living in multinational countries. The specifics of bilingual children cognitive development should be taken into account by the schools they study in, and the KIP initiative demonstrates the acknowledgement of this fact by the modern society. At the same time, there are also hidden KIP advantages that are connected to bilingualism and its influence on cognitive development and performance. In particular, it has been proved that bilingual children demonstrate better executive functions performance. CLS is the only school in Northern California to implement KIP for students in grades K-5, and to increase the parents’ awareness of the true benefits of the program, a study devoted to the advantages of bilingualism for children’s development will be carried out. The primary goal of this study consists in testing the ideas and assumptions concerning the positive impact of bilingualism on executive functions. However, increasing the parents’ awareness of the KIP benefits is also an important goal, and the population that we expect to benefit from this research is the students of the school who will be more likely to enjoy the advantages of KIP. The population addressed by this study includes Korean-English bilingual children while monolingual students are regarded as the control group. Three groups of students (in grades K-2) will be tested to gather information about their working memory, inhibition, and cognitive flexibility. The groups with include English-speaking monolingual children, Korean and English speaking bilinguals and those English-speaking children who have been participating in KIP for at least a year. We will attempt to gather enough pupils at the Claire Lilienthal School, but other San Francisco schools with similar demographics may also be involved. We expect the tests to be entertaining as they are going to be presented in the form of games designed specifically for children. The tests include the dimensional change card sort, the game “Simon Says”, the visually cued recall test, and the attention network task. Apart from the test results, other characteristics (age, socioeconomic status) will be gathered with the help of the parent questionnaire and school records. Additional characteristics are necessary to match the children’s performance correctly. The team of the study is yet to be established, but we understand that we need to take into account particular challenges. The study will require at least one Korean language specialist we hope to recruit from CLS staff. In general, we expect support and participation from CLS and KIP executives and members, and we are willing to include them in our team. We intend to evaluate the process of the study continuously with the help of the team members observation notes and databases. We allow the possibility of modifying the plan in the course of the stu