Roger Schank said this quote

Certain things need to be done again and again in life, but those things can be learned only in context, not as an abstraction. Different contexts must be provided in order to motivate students and to provide real world skills that will be remembered, not because they were studied and tested but because they were practicied again and again.

~ Roger Schank

I'm not suggesting that teachers never tell the truth, only that it isn't necessary to do it all the time. Since coming to one's own conclusions is mostly how we learn, the real job of a teacher is to force students to come to sensible conclusions by confronting what they already believe with stuff that is antithetical to those beliefs. A confused person has only 2 choices. Admit he is confused and doesn't care, or resolve the confusion. Resolving the confusion invloves thinking. Teachers can encourage thinking by making sure students have something confusing to think about.

~ Roger Schank

In summary, a good teacher does the following:- never tells a student anything that the teacher thinks is true- never allows himself to be the ultimate judge of his own students' success- teacher practice first, theory second (if he must teach theory at all)- does not come up with lists of knowledge that every student must know- doesn't teach anything unless he can easily explain the use of learning it- assigns no homework, unless that homework is to produce something- groups students according to their interests and abilities, not their ages- ensures that any reward to a student is intrinsic- teaches students things they may actually need to know after they leave school- helps students come up with their own explanations when they have made a mistake- never assumes that a student is listening to what he is saying- never assumes that students will do what he asks them to do if what he asked does not relate to a goal they truly hold- never allows pleasing the teacher to be the goal of the student- understands that students won't do what he tells them if they don't understand what is being asked of them- earns the respect of students by demonstrating abilities- motivate students to do better, and does not help them to do better- understands that his job is to get students to do something- understands that experience, not teachers, changes belief systems- confuses students- does not expect credit for good teaching

~ Roger Schank

... Let me start with the top mistakes that teachers make. Some of these mistakes are forced on teachers by a badly designed education system, and some are ones that teachers make no matter what they are teaching or which system they are teaching in. Some of these are less than obvious, so let's consider them one-by-one.1. Assuming that there is some kind of learning, other than learning by doing.2. Believing that a teacher's job is assessment.3. Thinking there is something that everyone must know in order to proceed.4. Thinking that students are not worried about the purpose of what they are being taught.5. Thinking that studying can replace repeated practice as a key learning technique.6. Thinking that because students have chosen to take your course, they have an interest in learning what you plan to teach them.7. Correcting a student who is doing something wrong by telling them what to do instead.8. Thinking that a student remembers what you just taught him.

~ Roger Schank