Teachers teach everything but not time mangement skills. Is that true? How can these skills to be taught in schools?

Yes it's true we have to plan a period for preparing competitive exam.its so helpful to time management because model paper will take on time

Best method give them the assignment and the time limit to finish that. the assignment should have to be finish in the given time and with maximum possible accuracy. this is how we are preparing our board going students. 

I think it depends on age and grade. Some teachers use time management during assignments and extra curricular activities and students usually pick up the idea. Also depends on teacher. 

Teacher's implicitly teach them the time management also by being becoming a real life example how one has to manage his time by strictly adhering to his schedules. And it is an individual's​ factor.

I think a good educator can do much more than just providing knowledge of a certain subject, a good educator can teach you about life, manners, management skills and can play an integral part in shaping charters and even future for his students  

no, the teachers teach students how to manage their time during the lesson by his planning of his time ,also assignments, quizzes and presentation .