How you can deal with the teacher is eligible to convey false information for pupils??

The simple answer is that they should not be allowed to teach, at best they might be employed as teaching assistants where they can gain valuable experience to enable them to work towards some form of qualification. This option would ensure that they were supervised by a qualified teacher and would therefore not be in a position to pass on "incorrect" information. Let's face it education is fundamental in starting youngsters off on life's journey and they have a right to expect the best that is available to them. It is also a big responsibility of local education authorities to ensure that non qualified personnel do not slip through the net and be put in positions whereby they can have an influence on how education and teaching is presented.;

Teaching is a task of great responsibility. I believe that the first attribute of a teacher is the realization of this responsibility and its sensitive nature. If a teacher has this attribute then he'll definitely acquire the necessary knowledge before tranferring it to the students. No one can claim a perfection in knowledge but the teachers have to learn it upto a level appropriate for teaching.

Seams to me that correct answer is somewhere in between local regulations and low and local practice - if corruption is big and if there is no governmental institution (if we are talking about public official education system) where you can raise a case for a concrete person - than all one can do is to explain this to kids, and tech what is proper. 

If question was raised here for matter of privately owned language schools - then reputation is what can change the things.  Complain to the owner, get arguments on table and demand better teacher for your kids.

Report them to the Board of Education as ineligible teachers. If they convey false information then they are  not qualified to teach. However the school should also know and a complaint should be filed to the Dean or Principal of the school.

It is question for school leadership.why it is allowed a person to teach who had no professional qualification. .....by the way that person is not even eligible to call a teacher. There is dire need to change leadership style and implement such polices and rules which give fruitful results and performance beyond expectation.