Access to international education has gained importance worldwide. In a globalized world, traditional education methods are found to be increasingly insufficient for educating well-rounded individuals who can contribute to their community. To the skills that will benefit students for the future with skills such as critical thinking or time management, more and more educators and parents believe that international education is crucial (Cole, Gannon, Ullman, & Rooney, 2014; Walker, 2012). More than just for internationally mobile students, international education has become important to any student who would like to acquire 21st century skills (Ramler, 1991; Rawlings, 2000).There are different curricula used in international education, the most common in Turkey in accordance with international standards is the Diploma Programme (DP) of the International Baccalaureate® (IB). The number of national and international schools that apply DP have increased rapidly in Turkey. The problem this study attempts to tackle is how the combination of international and national curricula helps Turkish students prepare for university education. Studies exist that have compared national and international programs by exploring the views of Turkish students, teachers, and administrators; however, the number of these studies is limited (Bora, 2010; Cam Aktas, 2013; Demirer, 2002). To understand the outcomes from the combination of national and international programs, the role of high school on university preparation needs to be investigated.The main purpose of this study is to evaluate student readiness and development for university preparation in Turkey through international education. In addition to the academic performance of students, their skills have been evaluated to understand their readiness and development for university preparation. The skills that were selected were time management and critical thinking. These variables were used to evaluate the differences between student outcomes. Research has indicated that study skills such as time management tie to the academic performance of university students (Proctor, Prevatt, Adams, Reaser, & Petscher, 2006). Critical thinking is described as an important skill in general education (Halpern, 2001) and is referred to as a 21st century skill (Partnership for 21st Century Learning, [P21], 2015). Changes in organizations require changes in educational experience and skills: More and more, employers and educators have indicated the need for better critical-thinking skills in academic performance and job outcomes (Koenig et al., 2011).In this study, the academic performance and skills of students who had attended the national high school program (MONEP) and IBDP were compared to students who had only attended the MONEP. Furthermore, the research investigated students' perceptions of their overall preparedness for university life through the questions listed below:a. How do university students' academic performances differ based on the high school program they attended?b. How do university students' skills related to academic performance differ based on the high school program they attended?c. What are university students' perceptions about their academic performance and skills within the university?International Baccalaureate Diploma Programme (IBDP)The IBDP is a two-year international education program for students between 16 and 19 years old. The aim of this program is to prepare students for university life. Its mission is to develop inquiring, knowledgeable, and caring young people who will help to create a better and more peaceful world through intercultural understanding and respect (IB, 2015a).The IBDP consists of six subjects: studies in one's native language and literature, language acquisition (secondary language), individuals and societies, mathematics, the sciences, and the arts. There are also three core components: Theory of Knowledge, Extended Essay, and Creativity-Activity-Service. …