Things that are counterintuitive

Relative humidity can be greater than 100%.
It's called supersaturation.

Even though hot air rises it can make air travel difficult.
Hot air is less dense and provides decreased lift
which is a problem at takeoff requiring longer takeoff runs per unit of speed and a greater speed before liftoff is achieved.
The Queens gambit is not really a gambit.
Material equalization can and frequently does occur rapidly.
A long or imperial ton is bigger than a metric ton.2240lbs. vs 2204.623 lbs. which itself is greater than a short ton 2000lbs.
Traveling faster than light is not forbidden.
But there is that darn mass/energy barrier.

You guys have any?
Things that don't quite sound right but nonetheless are true.

Loud intimidating people are generally acting out fear, and desperate to feel control any way possible.

Then a this bit in the bible Cor18 most counterintuitive 1st prize winner

thank God that I baptized none of you except Crispus and Gaius, 15 lest anyone should say that I had baptized in my own name. 16 Yes, I also baptized the household of Stephanas. Besides, I do not know whether I baptized any other. 17 For Christ did not send me to baptize, but to preach the gospel, not with wisdom of words, lest the cross of Christ should be made of no effect.

18 For the message of the cross is foolishness to those who are perishing, but to us who are being saved it is the power of God. 19 For it is written:

“I will destroy the wisdom of the wise,
And bring to nothing the understanding of the prudent.”

20 Where is the wise? Where is the scribe? Where is the disputer of this age? Has not God made foolish the wisdom of this world? 21 For since, in the wisdom of God, the world through wisdom did not know God, it pleased God through the foolishness of the message preached to save those who believe. 22 For Jews request a sign, and Greeks seek after wisdom; 23 but we preach Christ crucified, to the Jews a stumbling block and to the Greeks foolishness, 24 but to those who are called, both Jews and Greeks, Christ the power of God and the wisdom of God. 25

Because the foolishness of God is wiser than men, and the weakness of God is stronger than men.

26 For you see your calling, brethren, that not many wise according to the flesh, not many mighty, not many noble, are called. 27

But God has chosen the foolish things of the world to put to shame the wise, and God has chosen the weak things of the world to put to shame the things which are mighty; 28 and the base things of the world and the things which are despised God has chosen, and the things which are not, to bring to nothing the things that are,

29 that no flesh should glory in His presence.

30 But of Him you are in Christ Jesus, who became for us wisdom from God—and righteousness and sanctification and redemption— 31 that, as it is written, “He who glories, let him glory in the Lord

The cats
bleach works best cold water
Yo-yo
Free, land of the capital
alllll counter intuit, oh the count on sesame street!
...

American Football. :). lol

Antichess, trust me it’s the most counter-intuitive variant of all time

restaurant kitchen - check afirmate counter intuitivity
apartment kitchen - check negative counter intuitivity
multiply the reciprocal converse to natural inclination
(answer is invisible)

You can scare away a black bear by not being intimidated and making noise, even just clapping your hands. (You should also be careful not to corner the bear, however)

@Mrchess78 said in #3:

American Football. :). lol
They could have just called it soccer, that name wasn't taken and nobody else wanted it anyway but there you go :)

@The_Merry_Chesster said in #7:

They could have just called it soccer, that name wasn't taken and nobody else wanted it anyway but there you go :)

I literally just read that "Soccer" used to be called "Assoccer" using Oxford slang in the 20th century. :).

@Mrchess78 said in #8:

I literally just read that "Soccer" used to be called "Assoccer" using Oxford slang in the 20th century. :).
Lol, sounds a bit rude, doesn't it :)

@The_Merry_Chesster said in #9:

Lol, sounds a bit rude, doesn't it :)

But, amazingly it's true lol. :).