Advanced child tax credit payments are currently being sent out, and parents who qualify might be wondering about the best ways to put the money to use. If you've got your financial bases covered and are in a good position to watch long-term investments play out, there are opportunities to turn your cash into a much bigger sum. 

With that in mind, a panel of Motley Fool contributors has identified three promising growth stocks that could triple, or more, by the end of 2025. Read on to see why they believe that these stocks have what it takes to serve up incredible wins. 

A rocket launching from a person's hand.

Image source: Getty Images.

Tap into the ongoing advertising revolution

Keith Noonan (PubMatic): Digital advertising plays a huge role in powering many of the internet's most used applications and most successful companies. Whether it's data being collected to better target users with advertisements that are relevant to their tastes, or the actual placement and distribution of materials, ads make the World Wide Web go round. 

PubMatic (PUBM -3.08%) provides a platform that makes it easy for ad buyers to target their campaigns in accordance with real-time data. The company had its IPO last December and has seen volatile swings in subsequent trading, but the business is posting encouraging momentum, and its stock could deliver big wins for patient investors.

The ad tech specialist's revenue climbed 54% year over year in the first quarter to reach $43.6 million, and net income jumped from $0.9 million to $4.9 million. It also posted a dollar-based net retention rate of 130%, which means that customers using its platform increased their spending by 30% compared to the prior-year period.

PubMatic has a market capitalization of roughly $1.5 billion and is valued at about 7.7 times this year's expected sales. The company has also posted profits in its first two quarters as a publicly traded company, and the stock is priced at about 61 times this year's expected earnings. With PubMatic sporting a valuation that's still squarely in small-cap territory and operating in an industry that could continue to see big growth, risk-tolerant investors who take a buy-and-hold approach could enjoy strong returns.

If PubMatic can continue to attract new customers to its platform and get them to boost spending by demonstrating the value of its services, the stock stands a good chance of delivering explosive growth.

Don't make this common mistake with your $3,600

Jamal Carnette (Coupang): One of the more prevalent investing mistakes is home country bias, the tendency to only invest in domestic stocks. Although America is the world's largest economy, it comprises less than one-quarter of global GDP. Simply put, many U.S. investors are overlooking global opportunities, including e-commerce company Coupang (CPNG -1.49%).

Coupang has been referred to as South Korea's Amazon, partially because founder Bom Kim shares Jeff Bezos' relentless focus on the consumer. CNBC coined a different nickname for the company -- "Amazon Killer" -- when Coupang surpassed Amazon on its way to becoming the No. 1 e-commerce company in South Korea.

Beating Amazon is no small feat, but Coupang did just that by building a better logistical and fulfillment network. Forget Amazon Prime's two-day shipping, Coupang's Rocket Delivery service promises one day or less for 99% of its orders.

South Korea is perfectly situated for long-term e-commerce growth: The country's dense population is conducive to fast delivery with half all South Koreans living in the Greater Seoul region. Coupang aggressively invested in logistics, and now more than 70% of all South Koreans live within seven miles of a distribution center.

Additionally, the country boasts smartphone penetration rates higher than in the U.S., and has a well-educated and technology-literate populace with significant disposable income. If you're looking for a long-term growth stock for yourself (or your children) with the recent tax credit, look no further than Coupang.

This under-the-radar streaming start-up is a compelling buy right now

Jason Hall (CuriosityStream): It would be easy to assume that Netflix's plan to enter the video game market is a big indicator that the best growth days of video streaming are in the past. And to some degree, it's probably a fair assumption. But I think it's also a mistake to draw a line from Netflix's pivot to gaming to mean there aren't any opportunities for investors looking for big growth that should drive wonderful returns. 

That's especially true if it leads investors to ignore a small start-up like CuriosityStream (CURI 3.82%). Founded by Discovery Channel founder John Hendricks, CuriosityStream has an enormous library of more than 3,000 fact-based programs across nature, science, history, society, and more, with many in Ultra HD 4K. 

There's even more to like; unlike Netflix and other streaming peers, CuriosityStream is taking more of a hybrid approach. It offers direct-to-consumer subscriptions, but is also partnered with over a dozen other streaming providers including Hulu and Amazon (via its Prime Video) and bundled pay TV subscription access in more than 80 countries. In other words, CuriosityStream is making sure it's available wherever its customers are. 

And while this is a niche, it's a very compelling one that's delivering very fast growth. The company increased its subscriber count by 50% in 2020, and more than doubled revenue in each of the past two years. And on the back of a couple of recent Wall Street downgrades, investors can buy shares about 50% below the all-time high.