I love revenue growth -- it's one of my favorite financial metrics. But you can't look at that number in isolation. For instance, AMC Entertainment (NYSE: AMC) reported 2,252% revenue growth in its most recent quarter. But its massive debts and huge earnings losses make that stock a "no way" for me.

AMC gives us a clue as to why revenue growth might be spiking for many companies right now. Last year at this time, the COVID-19 lockdown was crushing a lot of stocks, with revenues dropping to near-zero for many companies. So the comps for movie theaters and hotels are spiking off the charts. While some of these stocks are "turn around" stories, all of the stocks in this article have strong financials and are way safer than AMC. Here's my list of five super-fast growers that ought to be wonderful investments going forward.

Cartoon businessperson with a jetpack flies past a businessperson climbing a cliff.

Image source: Getty Images.

5. Kahoot! -- 225% revenue growth 

Kahoot! (KHOT.F) is a Software-as-a-Service stock that's seeing amazing revenue growth right now as the demand for its educational tools spikes higher. The Norwegian company has a gaming platform that kids love. Using its software, educators can create fun and colorful multiple-choice trivia games in subjects like hard science or history.

To give one example, Kahoot! recently teamed up with Disney (NYSE: DIS) so that students have the ability to use Star Wars avatars like Yoda and Darth Vader. (Disney owns shares of Kahoot!)  

Kahoot! uses a freemium model, where the games are free to play. 1.9 billion people have played a Kahoot! game. Educators have used the free software to create over 100 million games. Almost a million users have become paid subscribers. The key for Kahoot is whether the company can convert its free riders into paying members. The high revenue growth suggests the company is succeeding. Educators -- both in schools and corporate training -- love the company's tools and are willing to pay more for optionality.

4. Airbnb -- 298% revenue growth

Airbnb (ABNB 0.09%) went public during the COVID-19 lockdown. The company is revolutionizing how we take vacations. Airbnb is a classic rule-breaker. It's the top dog and first mover in an important, emerging industry.

Airbnb is the internet hub for the bed-and-breakfast industry. The company has already achieved a $100 billion market cap, with over $4 billion in revenues and a price-to-sales ratio of 23. You might worry that a mega-cap like this might start hitting a ceiling in terms of how high it can grow. But actually, $4 billion is just a drop in the bucket for this BnB powerhouse.

Short-term vacation stays are a $1.8 trillion worldwide market. Add to that number the market for long-term vacation stays (over 30-day rentals), which is a $210 billion opportunity. And then add to that number another $1.4 trillion for experiences on your vacation. Ultimately Airbnb pegs its total addressable market to be $3.4 trillion. If Airbnb captures just a slice of this market, the stock will be a lot more valuable than it is today. With over 4 million Airbnb hosts around the world, the company has a vast amount of supply to meet our future travel demands.

3. IMAX -- 475% revenue growth

While AMC terrifies me, I continue to believe in the IMAX (IMAX -0.32%) story. One major difference between the two companies is that IMAX is a technology play. The company rents its large-screen apparatus to movie theaters around the world. And the company shares in the revenues when movies play on its giant screens. 

That's a terrific business model. You can just compare the debt loads to see what I'm talking about. AMC has a horrifying $11 billion in debt. If it used all of its cash to pay off debts, the company would still owe the banks over $9 billion. That's an ugly number, about 270 times worse than what IMAX owes ($34 million in net debt). 

Of course, IMAX screens often play in AMC theaters. IMAX shares its technology with theater chains around the world. In the second quarter, IMAX reported that it had 1,569 screens in 85 countries across the globe. The company already has twice as many screens in China as it does in the U.S.

In my opinion, IMAX is a safe way to invest in the reopening of entertainment as we emerge from lockdowns around the world. There are no debt issues here, and as a tech solution, IMAX will enjoy far higher margins than its industry peers.

2. Novavax -- 738% revenue growth

Novavax (NVAX -0.63%) is one of my favorite stocks, and it's been one of the strongest stocks in the world during the pandemic. The company is one of the leading vaccine manufacturers for COVID-19, although its solution is not on the market yet. Governments around the globe have already pre-ordered a couple billion doses of Novavax's vaccine candidate. 

Typically biotech companies have to get their drugs approved by the U.S. Food and Drug Administration (FDA) and other regulatory agencies before any revenues start rolling in. But COVID-19 is a strange situation. Governments are stockpiling the drugs ahead of time. The U.S., for instance, paid $1.8 billion to Novavax last year to pre-order 100 million doses of its vaccine candidate.

That's why Novavax has been receiving cash (and recognizing revenues) prior to its vaccine hitting the market. The company's already seeing tremendous revenues, even while its vaccine has yet to receive an emergency use authorization (EUA). While Novavax's revenue growth is sky-high right now, that's because it's jumping off a tiny base. Nonetheless, Novavax's amazing growth story is just getting started.

I'm expecting EUAs around the world to start escalating as we head deeper into the fourth quarter. And the future looks bright as well, with Novavax running a clinical trial in humans for its COVID/flu combo vaccine candidate. The small biotech is first out of the gate with a combo vaccine, so we'll see if it can keep its lead over mRNA competitors like Moderna (NASDAQ: MRNA) or Pfizer (NYSE: PFE) and BioNTech (NASDAQ: BNTX). An annual COVID/flu vaccination is a powerful long-term phenomenon, and right now Novavax is winning that race.

1. Park Hotels & Resorts -- 844% revenue growth

One doesn't normally think of a hotel chain as a "fast-grower." Hotels have to be built, after all, and that can take a year or more. Hotels have been around for a couple of centuries, and inns and lodges for many, many centuries. So it's kind of odd for a stodgy sub-sector like hotels to be growing so fast.

Of course, it's the COVID-19 lockdown that is responsible for these amazing numbers. During the worst of the pandemic, the hotels were completely shut down. And the stocks tanked along with this news.

Chart showing drop in Park's price since 2019.

PK data by YCharts

The stock for Park Hotels & Resorts (PK -1.08%) dropped all the way to $4 a share on March 18, 2020. The stock was a no-brainer at that point. Even in May, when the stock was $9 a share, it was pretty obvious it would spike a lot higher as the hotels reopened for business.

What about the future? I believe there will be near-term volatility in travel stocks, and you might get a cheaper share price over the next few months. While I don't love this hotel chain as much as Airbnb, I feel pretty strongly that our society will recover and these lockdowns will be a thing of the past.

When COVID-19 starts to wane, this stock will soon recover to its previous highs. The torrid revenue growth will slow dramatically, and the company will re-introduce its dividend. Park Hotels will be a safe, boring stock once again. (Although the stock will be dramatically higher than its share price now.)