What's some basic knowledge that a scary amount of people doesn't know?

Spelling and basic grammar. The "schools" are too busy filling the students' heads with political propaganda, perversion, and racism to bother teaching them anything useful.

How to grow a vegetable garden.

The meaning of the terms socialism and communism.

I got confusion between pull and push on doors😅

How to write a check.
How to craft a resume.
How to use a map.
How to write in cursive.

History! I refer you to Jesse Watter's man on the street, on the Fox channel at 7 pm EST, who asks random passers by questions about history, or even about current events, and it is both funny and sad how many people are woefully ignorant about their country and the world in general.

Social Security and Medicare will be Out of Money within 10 years.

He can’t even control his bowels

[quote]What's some basic knowledge that a scary amount of people doesn't know?[/quote]

What's some basic knowledge that a scary amount of people "don't" know?

That you’ve likely encountered a serial murderer or serial sex offender.

1) When to use an apostrophe.

2) How to add mixed fractions.

3) What "calibration" means.