Fools were out and about this week in an investing world jam-packed with actions and ideas. Here are three articles you might find useful as you decide how to invest your money.

Ask the Fool: Best Stocks for Young Investors
One of The Motley Fool's Twitter followers sought investing advice for young people with steady income. We responded.

Here's part of what Fool contributor Morgan Housel had to say: "Don't forget the secret weapon of compound interest. Work like a machine. Save like an animal. Whatever material luxuries you're forgoing today are probably trivial to the wealth you'll accumulate by starting young."

Click to the story to read the full advice given by three Fools and to see why they think stocks including Costco (Nasdaq: COST), Google (Nasdaq: GOOG), and Mosaic (NYSE: MOS) are worth looking into.

Tesla: A $1.33 Billion Pile of ... What?
You've had a few days to consider Tesla Motors (Nasdaq: TSLA) as a public company. It started selling shares to the public on Tuesday, and potential investors need to consider whether it can compete against the big wheels in the auto industry.

Little Tesla faces "a significant cost/price disadvantage, no experience in this kind of manufacturing, and with no disruptive new technology," Fool contributor John Rosevear wrote on Tuesday. "How do they win? For that matter, how do they survive? For investors, where's the upside?" asked John. He couldn't come up with a convincing answer.

Click to the story to see what other investors are saying about Tesla and add your two cents on whether it's a buy.

Don't Invest Before You Do This
You've set aside money you won't need in the next few years, you've opened a brokerage account, and you're ready to start buying stocks and funds. Well, hold your horses.

As Fool columnist Dan Caplinger wrote this week: "[I]f you skimp on all the work and preparation that should come before you write a check or push the buy button on your discount broker's website, then you won't get the results you need -- in large part because you won't even know what you need."

You might start by prioritizing your financial wants and needs; there's a difference between those two. Click to the story for more on how to be a good investor before you even buy your first share. Dan's also got an example of a model portfolio using ETFs.