Heaven is still the place where we teach.

Wang Bo, a great poet in Tang Dynasty, wrote "However, China keeps our friendship, and heaven is still our neighbor". Although it is used to describe the feeling of saying goodbye to close friends, it is also very appropriate to set it as the ultimate goal of distance teaching, that is, when implementing distance teaching, students who are thousands of miles apart must have the feeling of sitting together in class.

To create the feeling of "being close to the sky" in distance education, the stable transmission of sound and video is only the basic requirement of "necessary conditions", but also "sufficient conditions"-so that all participants in the classroom will not feel alienated from each other. Therefore, looking back on the development track of the whole distance education, we will find that the correspondence course originated from/kloc-0 in the early 1990s, and its learning medium was a single printed text delivered through the postal system. Then in the broadcasting teaching in the 1920s, I learned the media as words+sounds; In TV teaching in 1950s, the learning media was upgraded to text+sound+video. Although these three forms of distance learning lack interactivity, learners can only receive learning content from the teaching side in one direction, but the improvement of media richness will help enhance their interest in learning.

With the popularization of Internet in the 2 1 century, distance education began to adopt this brand-new information transmission channel, and the learning media was further upgraded to multimedia, and both teachers and students could have a question-and-answer dialogue, which improved the interactivity. This form of distance learning is not only widely used in personalized online learning, but also used by many schools to link the classroom teaching of the same course in different campuses, or to assist students in rural areas to obtain high-quality urban teaching resources.

In 2007, the research team of Taiwan Province Central University cooperated with Kaohsiung Education Bureau, and for the first time tried to collect the data of IRS instant feedback system scattered in different schools through the cloud, and launched a synchronous answering contest on the Internet. Its operation mode is to send IRS questions to classes in different campuses at the same time. After students sitting in these classrooms answer questions with feedback devices, the answer data is sent back to the cloud in real time, and the progress and achievements of each class are displayed on the webpage. This technology improves the remote synchronous interactive mode and lays the foundation for remote synchronous interactive teaching.

The first real long-distance synchronous interactive teaching class is the exhibition of the results of the long-distance teaching plan of the Ministry of Education of Thailand supported by online games information technology in Taiwan Province Province on 20 15. During the activity, students in three classes scattered in Bangkok, Buddhist Province and Chiang Mai used the video conference system to transmit videos, sounds and whiteboard teaching pictures, while students could use feedback equipment to answer questions from teachers of bishops in Buddhist Province, and the statistical data were displayed on the whiteboard pictures synchronously. This successful experiment makes distance education enter the era of synchronous interaction.

Distance teaching between classes in different schools can be divided into bishop end and participant end. The bishop refers to the teacher's class, and all other classes are participants. Therefore, the expression of distance education can be presented by adding two numbers. The former number represents the bishop and the latter number represents the participants, for example, 0+ 1. The former 0 means that there are no students at the bishop's side, only teachers, and the latter 1 means that there are 1 class students as participants. Another example is 1+2. The former 1 means that there are not only teachers but also students at the bishop's side, while the latter 2 means that there are two classes of students as participants. In the article "Remote Synchronous Interactive Teaching", the distance teaching form between Hong Kong primary school and Xiamen Yang primary school is 1+ 1, the bishop is in Hong Kong, the participants are in Xiamen, and the teaching unit is a third-grade English riddle. In addition, for example, the "Homesickness Hope Project, Remote Wisdom Chinese" public welfare plan jointly sponsored by Taiwan Province Science and Technology Leadership and Teaching Technology Development Association, Taipei South Asia Rotary Club and Taiwan Province Reading and Writing Teaching Research Association is also a 1+ 1 distance teaching activity with Chinese teaching as the core and the goal of improving the Chinese ability of homesick students.

Since remote synchronous interactive teaching helps to balance the educational resources between urban and rural areas, when a teacher with rich teaching experience serves as a bishop, is it true that the more classes there are at the participating end, the more this value can be reflected? The answer is not necessarily! Take a class of 30 students as an example. Under the mode of 1+3, the total number of students will reach 120, which has far exceeded the effective teaching load for a teacher to take care of all the students in the class as much as possible. Therefore, the effective remote synchronous interactive teaching mode is suggested to be limited to one of the following five types: 0+ 1, 1+ 1, 0+2, 1+2 and 0+3. In addition to the total number of students, video transmission is also greatly influenced by the network environment. The more classes, the worse the effect.

Four schools, Taibei Educated Youth Primary School, Hong Kong Students' Association Primary School, Xiamen Yang Zhai Primary School and Chengdu Ziteng Primary School, have held long-distance synchronous interactive classes in 0+3 language. The unit "The New Clothes of King Yas" was taught by Xu Huiling, a teacher of Educated Youth Primary School. In this "0+3" class, xu teacher is faced with a display screen showing students from other three places, so that she can clearly see the dynamics and reactions of all students.

Distance students can see the synchronous pictures marked by the teacher on the teaching materials on the electronic whiteboard, and another display screen shows the portrait pictures of the teacher and the reduced pictures of the other two classes. Seeing each other's pictures can establish a sense of meeting with everyone, and the synchronized electronic whiteboard pictures give students a real sense of participation in class.

In terms of student interaction, xu teacher requires all students to answer IRS questions, and then make up lessons according to statistical data, or randomly select students from each class to explain the reasons for their answers, and then other distance class students will evaluate or give feedback. This teaching strategy is to make students have a deep sense of interaction, so that students in different classrooms can also have a dialogue under the guidance of questions.

Cooperative learning in distance teaching is a great challenge for teachers. Many times, students need teachers' guidance, such as group activity design, homework assignment, activity development and assistance, and cooperation with students to complete assigned exercises to produce works. Therefore, it is very important to arrange assistant teachers in the participating classrooms. Teaching assistants accept the guidance of the bishop's teacher and provide necessary help for students' activities in time. The works completed by student groups can be sent back to the bishop teacher for comparative discussion through page transmission such as flat photography.

In this long-distance synchronous interactive classroom of "The New Clothes of King Yas" unit, xu teacher aimed at the second and third grade students in primary school, took picture books as the theme, combined with text reading and students' life experience, and went deep into the teaching core step by step through a clear teaching mode (speaking experience → picking key points → thinking, understanding and understanding → discussing and harvesting), training students' language ability of listening, induction, comparison, analysis and expression, and cultivating them.

In this attempt of remote synchronous interactive teaching in 0+3 mode, there are no "real" students in front of xu teacher, but students from three different classes are taught on one screen. Moreover, the students in these three classes have different growth backgrounds, study according to different curriculum outlines at school, and use two different Chinese fonts, simplified and traditional. She must consider these differences and create a real classroom teaching feeling instead of just sitting and listening passively. This is really a very big problem. Fortunately, for a teacher with rich teaching experience, he can still continue the past experience smoothly, and with a little adjustment, he can apply it to the new teaching situation and create new educational value.