Is it wrong to teach kids about Hell?

[Wyrd of Gawd]

That's the problem with religions especially ones like Christianity. Also...that's one of the very many reasons people still fall for it. Because they are worried of the consequence of hell.

But there is no hell, it's all made up.

Why? Well mostly for power and control over the masses.

There are countless hells on Earth.  Spending decades in solitary confinement is an American prison is hell.  People who were kidnapped, whipped, branded, and spent their lives in slavery were in hell.  People who starved to death while wars raged around them were in hell.  People disfigured and afflicted with all kinds of debilitating diseases and birth defects are in hell.  

There are countless hells on Earth.  You will be very lucky if you never experience one of them.  Billions of people have experienced them first hand.