There's a surprising tablet maker that's heating up this holiday season.

The publicly traded manufacturer has seen its stock more than double since its summertime low, so you know I'm not talking about Apple (Nasdaq: AAPL).

It's featured prominently on the front page of today's Wall Street Journal Marketplace section -- reporting that the tablet "has been selling online for up to twice its suggested retail price" after becoming scarce in stores -- but I'm not talking about those $99 Hewlett-Packard (NYSE: HPQ) webOS TouchPads. This is definitely not a discontinued tablet.

Critics argue that it's not a real tablet given its limited features, but I'm also not talking about's (Nasdaq: AMZN) Kindle Fire or Barnes & Noble's (NYSE: BKS) Nook Tablet.

If you're looking for a final hint, you may want to look at your kid's holiday wish list -- as long as it's a young kid's holiday wish list.

This frog's been a princely investment
LeapFrog's (NYSE: LF) LeapPad is a $99 learning toy geared toward kids between the ages of 4 and 9. Some of the tablet's features include a touchscreen, camera, and microphone. The "learning tablet" also has access to a growing ecosystem of apps that parents can download, though there are also dozens of plug-in cartridges offering games and books that can automatically adjust to a child's abilities. Yes, that's right. Even a book can immediately be fleshed out with more robust language if your child's reading skills advance. How cool is that?

Since it's a learning toy for children, you can probably guess the many tablet-like features that the LeapPad does not possess. There's no Facebook, YouTube, or Web surfing in general. Parents are the ones who can download the toy-specific apps, and LeapFrog has a special website for adults to track how their kids are progressing if they want to do that.

Older kids won't have anything to do with this rugged tablet. When "defeat Vader using reading skills" is the description of a Star Wars game, you know that this one is strictly for toddlers. The limited 2 gigabytes of storage also means that you won't be loading up the LeapPad with music or video. You can't, even if you wanted to. In so many ways, this is simply just the next evolutionary step in LeapFrog's line of high-tech learning gadgets.

What's in a name?
You have to give LeapFrog a lot of credit here. The fact that it's being positioned as a "learning tablet" at a time when tablets are all the rave makes LeapFrog's LeapPad a hot plaything this season. It doesn't seem to matter that it's a closer kissing cousin to THQ's (Nasdaq: THQI) uDraw -- the console-based tablet accessory that's selling so poorly that THQ's stock is getting slammed today after the company hosed down its holiday quarter guidance on uDraw weakness. Never underestimate the power of good marketing and seasonal buzzwords.

LeapFrog's had its share of highs and lows over the years. For every Leapster or LeapPad winner there's a Didj gaming system of Fly "pentop" computers that flops. The same thing can be said at the helm. A new CEO was brought in back in March.

Clearly something's going right with LeapPad. Even in the price-conscious realm of Wal-Mart (NYSE: WMT), the LeapPad was the retailing giant's most popular item on its layaway program as of mid-November.

I'm not surprised.

I put in a bullish call on LeapFrog in Motley Fool CAPS six weeks ago, and that pick is up nearly 60% in that time. In the spirit of our CAPScall push for accountability, I'm going to stick to that position. Hot holiday toys may be fleeting fancies, but I think the LeapPad ecosystem of digital apps and plug-in cartridges will keep this one going well into 2012.

We can argue about what defines a tablet, but a hot stock is a hot stock.

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This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.