If God Is So Good, Then Why Do Bad Things Happen?

I've researched this a lot. This is question asked re: ALL religions. It seems to be the #1 argument Atheists use. Personally, I find it childish. But, they really seem to hold onto it!

"If God really exists, then why does he let bad things happen?"

The following is just my personal opinion after hours of thinking. I think each religion has their own take on it. Basically...

- It's a system of checks and balances, bad HAS to happen with the good.
- We learn through the bad (think about it - it's always a better teacher than good).
- With no bad, how do you know that which is Good.
- During bad times, we always pray and get closer to God.
- Bad seems to be when we talk the most with God.
- Some Religions: The person or person(s) brought it upon themselves through Sin

Basically it says that God isn't there to shelter us from bad. As a Good Father, he actually would be dis-serving us. We need to learn to walk. The process includes falling.

Anything you want to add to this?