What toys won over the toughest critics at Toy Fair?

On the crowded floors of the Javits Center, toymakers are pitching their products this week at New York Toy Fair.

From interactive Barbie dolls that hold two-way conversations to drones and other gadgets, the industry is trying to create buzz and woo parents. But at the end of the day, the toughest critics are tech-savvy kids who can often see past the hype, and just want to have a toy that's fun.

With that in mind, CNBC hit the show with two pint-sized analysts in tow, to find some of the hottest toys that kids will really want to play with.

Among the toys that put smiles on the faces of 7-year-old Noa Suied and 6-year-old Vincent Scolaro were new lines from K'Nex, called Mighty Makers and K-Force Build and Blast.

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Mighty Makers is a line of construction toys targeted to girls ages 7 and up. The building sets, which include a Ferris wheel and a greenhouse, encourage girls to build and then role-play, while K-Force is all about building and blasting. The K-Force line includes eight different kinds of blasters, buildable targets and foam dart packs.

Sales of building sets have been growing robustly in recent years, even as other categories of toys struggled. Last year, U.S. retail sales for the whole toy industry increased 4 percent to $18.08 billion from $17.46 billion in 2013, according to market researcher The NPD Group. Within that, the building-set category saw the fastest growth, with sales up 13 percent, NPD said.

CNBC mini analysts Noa Suied, 7, and Vincent Scolaro, 6, test and review new toys at the K’NEX booth at Toy Fair on Monday, February 16, 2015.
Mary Stevens | CNBC
CNBC mini analysts Noa Suied, 7, and Vincent Scolaro, 6, test and review new toys at the K’NEX booth at Toy Fair on Monday, February 16, 2015.

Much of the strength has been fueled by the Lego brand, which overtook Ferrari this year as the world's most powerful, according to a ranking by brand valuation and strategy consultancy Brand Finance. The group cited the popularity of "The Lego Movie" as one factor for its high score.

"In a tech-saturated world, parents approve of the back-to-basics creativity it encourages and have a lingering nostalgia for the brand long after their own childhoods," Brand Finance said in a press release.

But nostalgia doesn't always win the day. Parents may have fond memories of playing the Simon memory game, but a reboot of the brand didn't win over CNBC's toy testers.

The same goes for licensing. Licensed toys represent 31 percent of total toy industry sales and the category saw an increase of 7 percent in 2014 compared with 2013, NPD said. Much of the growth came from the popularity of Disney's "Frozen," which was the top gainer among all toy properties last year based on absolute dollar growth.

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"Frozen" is still popular, but the upcoming short "Frozen Fever," which will be showed before the "Cinderella" live-action movie, will likely keep the interest going.

Toymakers also have several other big films to play with, including the next "Star Wars" movie, the upcoming "Jurassic World" and "Avengers: Age of Ultron."

The equivalent of more than seven football fields filled with brand-new toys and games were unveiled in New York City at the 112th North American International Toy Fair taking place February 14-17, 2015 at the Jacob K. Javits Convention Center in New York.
Cem Ozdel | Anadolu Agency | Getty Images
The equivalent of more than seven football fields filled with brand-new toys and games were unveiled in New York City at the 112th North American International Toy Fair taking place February 14-17, 2015 at the Jacob K. Javits Convention Center in New York.

Not all licenses are tied to the movies. Wicked Cool Toys is trying to tap the power of the Girl Scout brand with its new toy oven, Girl Scouts Cookie Oven. Although CNBC's toy testers loved the cookies, they felt the actual toy wasn't that much different from other toy ovens on the market.

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Instead, they were bigger fans of Tokyo-based start-up Moff's Moff Band, a wearable smart device. Kids can slap on the Moff band, connect it to an app on an iPhone, iPad or iPad mini, then its accelerometers and gyros go to work sensing the range of movement the wearer makes. The movement is then translated into various sounds so that kids can act out playing a game of tennis, fighting with swords, or strumming on an air guitar.

CNBC's toy testers were also won over by new additions to Hexbug's Aquabot line. They include a robotic jellyfish and sea horse that can swim in a bowl of water. To save battery life, these critters will turn themselves off after a few minutes; but if you want to keep the show going, simply tap on the tank or run your fingers through the water and they will spring back to life.