This country is fully committed to the introduction of computers into schools. This is demonstrated by the fact that virtually all 600 high schools and about one-third of the 1 600 elementary schools are now using computers in one form. or another. Another third of the elementary schools are actively working to acquire computers. In addition, all teachers and college students must participate in at least one basic computer course. The main support for acquiring, maintaining and operating computers in schools has come from the 'Educational Welfare Program' of the Ministry of Education, which is similar in many ways to Title I in the United States, and from the educational branch of 'Project Renewal', which is concerned with helping extremely poor neighborhoods and towns both physically and socially. As a result, most computers are found in schools with many disadvantaged pupils. For example, the first school computer system was introduced in Netivot, which is a small development town in Negev Desert. The situation is now changing, support provided by the Educational Welfare Program and by Project Renewal is reducing and parental contributions are being used to purchase computers in schools with many advantaged pupils. However, some of the slack (松懈,减弱，减缓)created by reduced government support will be taken up by support from the national lottery (彩票), and it is likely that such support will be channeled largely to schools with many disadvantaged pupils. Control of government funding for software development, teacher training and purchase of equipment is centralized in a high-level committee of the Ministry of Education. In recent years about 50 percent of the funding went for the development of basic computer courses by various universities and teachers colleges. About 30 percent went for general curriculum development and 20 percent went for purchase of equipment by schools and teachers colleges. The number of the elementary schools to which computers have not yet been introduced is about______.