This is Planet Money from NPR.

Hey everyone, welcome back to Planet Money Summer School.

Today's class number three, Smooth Spending and the 401k.

I'm Cardiff Garcia and in the first two summer school classes,

we looked at the stock market and had a pick stocks

and we will get to other markets in the next episode.

But today we are learning an investing lesson that should matter to everyone,

including people who right now are left out of the stock market.

Now as we've said throughout summer school,

investing is about turning money now into more money in the future.

But investing is also about making sure that you have the money you need when you need it.

Would you have enough money to fix your car if it broke down tomorrow or in a year?

How are you planning to pay for your kids' college?

Do you have a lot of debt to pay off?

How old do you want to be when you retire and do you want to leave money behind for your kids to inherit?

In this class, we are going to talk about investing strategies for planning across your whole lifetime.

And the challenges you're likely to face in doing that.

So for this class, I am joined once again by our Planet Money Summer School professors,

Allison Trigger of the Manhattan Institute.

Hey, and me here they sigh of Harvard Business School.

Great to be back.

So in our first summer school class, we said that investing was about sending money into the future.

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