Teach people it is okay to ask questions. Teach people to be tolerant of those with differing opinions.

I believe teach them the fallacies EARLY and use flash cards to see if they can identify them. Many people that have taken critical thinking, or claim to teach it often resort to a lot of the logical fallacies when pushing their own ideas. So teach kids to identify such things.

Appeal to Authority / AKA Argument from Authority
Appeal to Emotion / AKA Argument from Emotion
Appeal to Popularity / AKA Bandwagon
Appeal to Tradition
Appeal to the Stone (this one is important and many people have no clue about it)

Then you can play mental games of tag using things like Red herring, Ad hominem, Slippery Slope, etc.

Appeal to Authority is a VERY important one.

People often use AUTHORITY to shut down discussion even if that "authority" is wrong, or partially wrong.

Also one VERY important thing. Teach kids that it is okay and even a good thing to be wrong. People who are rarely wrong in reality are just people who are not learning much.