Our children will not gain strength if we protect them from such things as...

Knowing how much you love them

The acknowledgment of your own imperfections and mistakes

Challenges

Hard work

Decision Making

Sacrifice

Necessary Confrontations/Standing Alone

Consequences

Noticing the consequences of sin in other’s lives

False teachings (Compare instead what man says to what God says in scripture)

People from other ethnicities or cultures or other income levels

People who are grieving or people who are dying

...and of course wise parents much mindfully select when it is safe and compassionate in the above circumstances to bear the weight of the situation...

But does God recommend exposing our kids to the evils of the world in order to somehow build some kind of immunity?”  Actually, God says “Do not be deceived: "Bad company corrupts good morals." 1 Corinthians 15:33 and  “He who walks with wise men will be wise, but the companion of fools will suffer harm.” Proverbs 13:20

Of course, no amount of sheltering takes away the free will of a child, but with some creativity,  one can provide for their children a very active social life while putting forth our most conscientious efforts to provide an environment where souls can flourish.