The best way to teach people critical thinking is to teach them to write. Because there's no difference between that and thinking.
One of the things that blows me away about universities is that no one ever tells students why they should write something. "Well, why are you writing?" "Well, you need the grade." It's like, no! You need to learn to think because thinking makes you act effectively in the world. Thinking makes you win the battles you undertake - and those could be battles for good things. If you can think, speak, and write, you are absolutely deadly.
Nothing can get in your way. So that's why you learn to write. And if you can formulate your arguments coherently, and make a presentation, if you can speak to people, if you can lay out a proposal. People give you money; they give you opportunities; you have influence. That's what you're at university for. Be articulate. Because that's the most dangerous thing, you can possibly be.