TORONTO - The big thrill in watching the U.S. game show "Are You Smarter Than a 5th Grader?" is seeing adults struggling with basic elementary school questions in front of a studio audience and know-it-all kid "classmates."

What viewers don't get to see is the turmoil the host can sometimes go through as well, says Colin Mochrie, who helms the five Canadian episodes of the show, the first of which airs Thursday on Global.

"I have no idea what the questions are (in advance)," Mochrie confessed in a recent interview outside the Toronto studio where the five episodes of "Are You Smarter Than a Canadian 5th Grader?" were taped.

"In fact, for me, that's my major source of tension - that when the questions come up there's going to be a word I've never seen before and it's like, 'Oh, GOD, please help me!' because I get a word wrong and immediately there's (seven) kids yelling at me, making fun of me," he said.

"I'm not kidding. They just jump on any kind of weakness. They're like a pack of hyenas and I'm just the big chicken that they're ready to tear apart."

Mochrie would seem a natural choice to host the Canadian version of the show. A veteran of improvisational comedy, he has the sharp wit and charm to prod the adult contestants when they're trying to match their smarts against seven wily kid panellists for a chance at winning $1 million.

Yet Mochrie himself didn't know if he was right for the role when he was approached to do it earlier this summer.

"I was actually a little worried about taking this job," said the Toronto-based actor.

"I'm very used to being part of an ensemble and usually that ensemble are all my friends so it's very relaxed for me and I wasn't sure whether hosting was something I'd be able to do and I didn't realize how hard it was until I was sort of thrown in the middle but it turned out great."

The format for "Are You Smarter Than a Canadian 5th Grader?" is similar to the U.S. version, but includes all-Canadian questions and a Canuck set. The homegrown version also has seven kid classmates instead of just five that the U.S. series has.

Mochrie said he only knew the answers to "a good three per cent" of the questions, partly because there were references to things he'd never learned in school, like the metric system and Nunavut.

"As soon as I see those, my brain shuts off and I glaze. I glaze and then as I'm reading the question I go, 'Ah, I've lost interest in this, I don't know what it is. Hope you do win the money!"' he said.

"Sit back, let it happen, that's the beauty of this. I'm drunk half the time anyway so it really doesn't - no, that's not true."

Now that he's gone through the experience, Mochrie says he'd gladly do it again - even take it on full-time, if offered.

"I could be the Bob Barker of the Grade 5 set," he joked.

The comment has some merit considering Mochrie's former "Whose Line Is It Anyway?" colleague Drew Carey has taken over the retired Barker's role on "The Price Is Right." Wayne Brady, another "Whose Line Is It Anyway?" cast member, has also gone the game show route with "Don't Forget the Lyrics."

The adult contestants in "Are You Smarter Than a Canadian 5th Grader?" include a university professor, a nuclear engineer, an air traffic controller, an occupational therapist, a lawyer and an Anglican priest.

Mochrie, of course, couldn't reveal how big the winnings were but did say that while "Some people won large amounts of money," most contestants played fairly conservatively.

"They don't like to risk the big money and go for the million," he said.

"They tend to go, 'OK, this is a good amount,' and I think that's what Global executives are hoping for. Should I be saying that? Oh well, oh well, what are they going to do, fire me?" he said laughing.