A、Identifying the best teachers nationwide. B、Improving the quality of teaching and decision-making. C、Promoting the use of effe

In recent years, Bill Gates has given financial support to improve American education. Last year, the Bill and Melinda Gates Foundation launched the Measures of Effective Teaching project. The project tests new ways to recognize what makes a good teacher. Its goal is to help educators and policymakers identify and support good teaching. The study is being carried out in public school systems in seven American cities. Thousands of teachers volunteered to take part. They agreed to have their classes recorded on video, but only for observation by expert researchers. Researchers also collected information from students. They asked students to report their opinions of each teacher’s class. Students were also tested in Mathematics, English and Biology. Officials recently released early results of the project study. The report says teachers’ past success in raising student scores on state tests is one of the strongest signs of their ability to do so again. The results also say students know effective teaching when they experience it. Another finding shows that combining different sources of information helps administrators provide better comments and suggestions for teachers. In many cases, administrators had been basing their comments on students’ test scores only. The Measures of Effective Teaching project continues through 2012 when final results will be released. Researchers plan to test a new measure that examines what a teacher knows about how to teach a subject. Experts say these findings could also help create better training and development for teachers.
Questions 20 to 22 are based on the passage you have just heard.
20. What is the Measures of Effective Teaching project aiming at?
21. What did teachers agree to do in the project?
22. What does the project study find?