It's not easy to pick a stock portfolio that will beat the market average: most mutual fund managers don't, and they're supposed to be pros. But using Motley Fool CAPS, anyone can try their hand at stock picking, and get ranked over time based on how well they do. One early CAPS stock picker -- he began when he was 8, back in 2007 -- was Motley Fool co-founder David Gardner's son Zack.
Is it possible that the logic of a child can beat the numbers and rationale of traditional adult stock pickers?
In this week's Rule Breaker Investing podcast, Zack is his dad's special guest, as they review his hits, his misses, and why he chose the stocks he did. In this segment, they cover his very first pick: Marvel, a stock pick that did, well ... super.

A transcript follows the video.

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This podcast was recorded on July 5, 2016.

David Gardner: Now I mentioned tens of thousands of people have used CAPS over the years to rate stocks and be rated themselves, and one of those people in 2007 was, at the time, an 8-year-old boy. He is my son Zack, my youngest child, and he's my special guest here on our July 5 Rule Breaker Investing podcast. Zack, welcome.

Zack Gardner: Thank you for having me.

David: So Zack -- you and I -- here's what we did. We'd started CAPS. You know that I'm passionate about everybody investing, including kids. And one of the things we've always tried to do at The Motley Fool (we've written an investing guide for teens) is try to get people started as early as possible.

So there you and I were, at home, sitting in front of the PC. It was even a PC, at the time, not a Mac, because we didn't flip over to Mac until 2008. But we were sitting in front of my PC. You weren't necessarily typing that well. (Would you say you were an investor at the time?)

Zack: Oh, definitely not.

David: Definitely not. But you and I talked about the stock market and that you can be a part-owner of companies. So from January 2007, when you made your very first pick -- you've made a number since then -- in each case, I asked you why. Why did you pick that particular stock? For example, the very first stock you ever picked: the day was Jan. 10, 2007. Do you remember what that stock was?

Zack: I don't think I do. You'll have to tell me.

David: Marvel. It was Marvel Enterprises (Marvel Comics at the time). I insisted, Zack, that you tell me (a little 8-year-old kid) why. "What is it, Zack? Why are we picking Marvel today?" And I would type in your answers verbatim. You said at the time, "Because we have the board game, which is quite good, and it makes really good video games. My favorite superhero is Thor."

So what we're going to do on this week's special podcast is we're going to go back over some of your hits and misses. We're going to review what you were saying at the time. We're going to see what's happened 10 years later, and what lessons we can learn. Are you ready?

Zack: Let's go.

David: Are you game?

Zack: Always.

David: All right, good. Do you remember what the board game was that you were talking about, there?

Zack: Honestly, I don't know. I could probably recall the video game, but the board game is going to be a hard one.

David: It was "Marvel Heroes." It's a cooperative board game that I bought at the time, and for you, since we were not big comic book readers -- I don't remember you reading a lot of comic books -- it was more about the games we were playing. We had a number of Marvel video games as well. My other question for you is, before we get to the next one, is Thor still your favorite superhero?

Zack: I think I'm going to have to go with "yes."

David: Go with "yes."

Zack: I mean, if we were looking at the movies, maybe Iron Man, just because Robert Downey, Jr. plays the part incredibly well, but you can't argue with Thor. I mean, the dude's a god.

David: Good point. And speaking of "godly," you killed it with this pick, as you will well remember. Marvel has since been bought out by Disney (DIS -0.55%). That happened on Aug. 31, 2009; Disney paid $4 billion. The transaction actually consummated in 2010.

In fact, the very first day, Jan. 1, 2010, you were closed out of that position on CAPS. The stock had gone from $27 to $54, so you were up 98%. The stock market over that same two-year period had declined 21%. And you know this: In Motley Fool CAPS, we take the return that you get for the stock versus the stock market, so your stock's up 98%, market down 20%, so you got 119 points to kick off your CAPS scorecard. Pretty promising, right?

Zack: Yeah. I wish it was all that good.