With the changing times and across levels of education, one thing that might have remained constant is that good teachers always teach how to think instead of being just the source of information on what to think. They use all the resources around them to help student's build their personalities. The goal of education cannot be mere preparation for earning livelihood in future. Coaching and training are enough for that purpose and anyone with proper access to the information can gain enough knowledge to earn a living. Better society is not formed by better earning future generation alone, it is formed by better ideas, innovation and evolution of human values, generation after generation.
Given the technological advances and access to enormous information, students of 21st century are not dependent on formal coaching for making ends meet. Before a teacher starts teaching a topic in classroom, some of the students may already have number of different pieces of information on the topic which may very well be differing from the textbook version of the facts, not any particular of them being necessarily the correct one. This makes the role of teachers in the process of education of 21st century even more critical and challenging.
In the vast sea of information, teachers first need to learn fast on their own, be updated on the various perspectives on the same topic, learn from the students, and above all of this, they need to be the guides who will ensure that the learners are going in the right direction while surfing through all the information. While technology brings lot of resources for teachers, it also makes their role even more challenging. The more reluctant teachers are to adapting this change, the more directionless will be the future generations.
So should the teachers gain a lot of knowledge? Should they really know which direction is correct for each of the students? That would fairly impractical and inefficient. So while being updated on the teaching resources, the teachers need to be able to guide and mentor their students on certain basic values which will help them filter the information for its rationality, correctness, interest, ethics and practicality. There would be more such basic values and each teacher needs to develop them on their own. But once the students get the sufficient 'coaching' on these while learning the set courses, there is more likelihood that they would neither be lost in the amount of content, nor be restricted in their perspectives. This would further help them be more self-driven, innovative and practical. Once these values are imbibed, they would be sufficiently equipped to both sustaining a livelihood as well as making a better society of their own.
Teachers need not just remain the source of information, either from textbooks or from internet, either on paper or on the screen, they just need to provide proper pointers on what to look out for, how to filter that, and further encourage its practical use by means of 'creating' various kinds of useful resources from that. For doing all these, they can very well make use of the technology solutions, which facilitate creationism, collaboration, prototyping, and automation for the mundane tasks.