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Gravitational waves from black-hole merging events have revealed a population of extra-galactic BHs residing in short-period binaries with masses that are higher than expected based on most stellar evolution models - and also higher than known stellar-origin black holes in our Galaxy. It has been proposed that those high-mass BHs are the remnants of massive metal-poor stars. Gaia astrometry is expected to uncover many Galactic wide-binary systems containing dormant BHs, which may not have been detected before. The study of this population will provide new information on the BH-mass distribution in binaries and shed light on their formation mechanisms and progenitors. As part of the validation efforts in preparation for the fourth Gaia data release (DR4), we analysed the preliminary astrometric binary solutions, obtained by the Gaia Non-Single Star pipeline, to verify their significance and to minimise false-detection rates in high-mass-function orbital solutions. The astrometric binary solution of one source, Gaia BH3, implies the presence of a 32.70 \pm 0.82 M\odot BH in a binary system with a period of 11.6 yr. Gaia radial velocities independently validate the astrometric orbit. Broad-band photometric and spectroscopic data show that the visible component is an old, very metal-poor giant of the Galactic halo, at a distance of 590 pc. The BH in the Gaia BH3 system is more massive than any other Galactic stellar-origin BH known thus far. The low metallicity of the star companion supports the scenario that metal-poor massive stars are progenitors of the high-mass BHs detected by gravitational-wave telescopes. The Galactic orbit of the system and its metallicity indicate that it might belong to the Sequoia halo substructure. Alternatively, and more plausibly, it could belong to the ED-2 stream, which likely originated from a globular cluster that had been disrupted by the Milky Way., Comment: 23 pages, accepted fro publication in A&A Letters. New version with small fixes

This report will determine to what degree the AP Physics 1 and 2 and AP Calculus AB and BC frameworks are aligned with the Trends in International Mathematics and Science Study (TIMSS) Advanced Physics and Mathematics frameworks. This will enable an exploration of any differences in content coverage and levels of complexity, and will set the stage for a future performance report that will evaluate AP student performance on TIMSS Advanced. The current report will expose meaningful differences in frameworks that may speak to performance outcomes. In 2015, the U.S. as well as several cooperating countries will participate in TIMSS Advanced, providing the optimal opportunity to recognize AP and non-AP students within the TIMSS Advanced sample and investigate the differences in performance. The field trial determined that the established sampling plan ensured adequate AP Physics 1 and 2, and AP Calculus representation, as well as non-AP students to which they can be compared for the final country-to-country performance report. The overall strong alignment between the TIMSS Advanced framework and AP Physics 1 and 2 and AP Calculus suggests that AP students taking the TIMSS Advanced Exam in the Spring of 2015 should be very familiar with the content being assessed. Further, AP students should also be familiar with the context of the assessment items and the way in which the assessment items are presented to the students on the exam. Knowing that AP students are prepared for the TIMSS 2015 Exam will allow for deeper claims to be made in the subsequent performance report, as it will not be necessary to speculate whether or not the material on the TIMSS Advanced 2015 Exam is relevant to AP students. In addition, the level of detail this alignment report provides will allow researchers writing the performance report to deconstruct different sections of the TIMSS 2015 performance report to identify sections of the exam where we would expect AP students to excel and where AP students are less prepared for the content being assessed.

Educators are increasingly focused on ensuring that students experience a rigorous curriculum in high school and graduate college and career ready. One way of introducing rigorous course work is to have students take college-level work, often in the form of either an AP® course and exam or a dual enrollment course. This study compared the outcomes of students who participated in either program and graduated high school in 2006. The outcomes investigated were four-year college enrollment, persistence at a four-year institution, graduation in four years, and graduation in six years, as well as first-year college grades. The results indicated that AP students who had obtained at least one score of 3 or higher on an AP Exam considerably outperformed on all examined outcomes except for four-year college enrollment, which was highest for students who had taken a dual enrollment course affiliated with a four-year college. AP students whose highest exam score was less than 3 performed as well or better than did students who took a dual enrollment course affiliated with a two year college for all outcomes. AP students whose highest exam score was lower than 3 outperformed students who took a dual enrollment course affiliated with a four-year college on some outcomes and underperformed on others. Tables are appended.

Many articles and reports have reviewed, researched, and commented on international assessments from the perspective of exploring what is relevant for the United States' education systems. Researchers make claims about whether the top-performing systems have transferable practices or policies that could be applied to the United States. However, looking only at top-performing education systems may omit important knowledge that could be applied from countries with similar demographic, geographic, linguistic, or economic characteristics--even if these countries do not perform highly on comparative assessments. Moreover, by exploring only the top performers, a presumption exists that these international assessments are in alignment with a country's curricular, pedagogic, political, and economic goals, which may falsely lead to the conclusion that by copying top performers, test scores would invariably increase and also meet the nation's needs. While international comparative assessments can be valuable when developing national or state policies, the way in which they are interpreted can be broadened cautiously to better inform their interpretability, relevance, and application to countries such as the United States--all while considering the purpose of each international assessment in the context of a nation's priorities. Ultimately, this report serves as a reference guide for various international assessments, as well as a review of literature that explores a possible relationship between national economies and international assessment performance. In addition, this review will discuss how policymakers might use international assessment results from various systems to adapt successful policies in the United States. Tables are appended.

Every year in the United States, millions of students graduate with some type of postsecondary credential--certificate, associate, or bachelor's degree--and discover they are not, or are identified as not being, adequately prepared to compete in the increasingly global economy. A recent McKinsey & Company study, Education to Employment, reported that less than half of U.S. student respondents believe their postsecondary studies improved their employment opportunities and half of U.S. employer respondents say a skills shortage is a leading reason for entry-level vacancies--and this trend is worldwide. By 2018, the United States will need approximately 22 million new Associate's degrees or greater to fill new and replacement job projections, but will have three million fewer postsecondary degrees than needed. This reality brings forward the question: How do we ensure that those with a postsecondary credential are prepared for a rapidly changing and globalized economy? A first and necessary step is the Common Core State Standards (CCSS), which, at this time, have been adopted by forty-five states, the District of Columbia, four territories, and the Department of Defense. As is well-documented, CCSS raises college and career readiness expectations for all students in the United States. Curricula, assessments, and teaching, however, will need to include and integrate global competency skills to ensure that students are prepared to succeed in the workforce. Toward that end, this brief is intended to support educators in preparing the next generation of students for college and career in an interconnected and hyper changing world by highlighting key, relevant concepts germane to comparative education.

In recent decades, the United States economy has undergone a dramatic shift to a knowledge-based economy that, when coupled with simultaneous, rapid globalization, has created a greater demand for a more educated and skilled workforce. The share of U.S. jobs requiring some level of postsecondary education is expected to grow to 63% in the next decade. By 2018, the United States will need 22 million new college degrees and at least 4.7 million new workers with postsecondary certificates, but it will produce three million fewer degrees than are needed. Evidence suggests that a substantial fraction of the student population in the United States is insufficiently prepared for postsecondary education, which results in a great cost to the nation. Students' performance on the National Assessment of Educational Progress (NAEP), a nationally representative assessment, is an indication of the challenges that states face in trying to prepare students for postsecondary education. For example, 2009 NAEP data indicate that just 38% of U.S. 12th-graders performed at or above proficient in reading, and only 26% performed at or above proficient in math. Data from international academic assessments indicate that students in the United States are being outperformed by other developed nations. On the Programme for International Student Assessment (PISA), 15-year-olds in the United States ranked 17th in reading and 31st in mathematics. Secondary and postsecondary institutions must address the academic rigor of their programs and why students are not successfully completing postsecondary programs. This brief is intended to support policymakers in achieving the goal that every student graduating from high school is ready for both college and career.

Following the completion of this century's first decade, educators, policymakers, and researchers are attempting to predict future needs. However, is it possible to know what the education and global landscape will look like at the end of this century? Certainly, in 1900 one could not have comprehended the myriad innovations that would occur by the year 2000. What we know is this: The skills to survive and thrive in this century have transitioned from a memorizing or banking perspective to that of accessing, navigating, and filtering. Moreover, the primacy of technology to our daily lives and events and phenomena across the globe cause many to rethink how best to prepare students in an education system born out of Prussian and industrial-era influences. Of additional importance for American education, comparative assessments demonstrate that other nations have surpassed the U.S. when it comes to preparing their students. This dynamic must inspire innovative solutions to improve American education. But, because demographic, linguistic, vocational, economic, and political variables differ from country to country, we cannot simply copy systems that outrank or outperform the U.S. Also, solutions must be developed to support a balance between competitive and collaborative reform efforts. While many obstacles exist, including cultural, economic, and political considerations, with the appropriate framework, organizations such as the College Board can support U.S. education systems (at the local, state, and federal levels) to maintain relevancy amid a shifting paradigm. Moreover, organizations such as the College Board can concurrently increase access and equity to provide more students with greater opportunities to learn and then contribute to the national well-being. As this paper will explore, at the heart of this movement will be the adoption of global skills in curricula, assessments, and pedagogy. Thus, while we may not know what the education and global landscape will look like in 2100, students who benefit from this reform movement globally will be prepared to excel and succeed. Appendices include: (1) International student origins; (2) 10-year job trends underscore shift to service sector; (3) Global Literacy Education in Practice; (4) Examples of assessment measures; and (5) Major Frameworks for 21st Century Learning.