I teach critical thinking. There are 4 stages. The first is called duality, which is right or wrong. The book or teacher is right and you have to learn is said or read. The second stage is called "it's all relative" and may seem a regression, but it is a phase of questioning. The third stage is a good stage of crirical thinking where logic, sources, evaluation of evidence, consistency, conclusion, reliability and validity are examined. The fourth stage is the third stage with a little added in terms of a personal intellecual identity coupled with an awareness of limitation. A really good source is Bean (2011). The book is called Engaging Ideas.
