LONDON » The gymnasts on the U.S. women’s team giggle like the teenagers they are as they show off their stash of Olympic pins.

A "fave," says team captain Aly Raisman, is the one from Kellogg’s cereal. "Snap, crackle and pop" is a slogan almost no American can ignore, so don’t blame the girls for their Kellogg’s love.

And expect them to perform with equal amounts of snap, crackle and pop today when the women’s gymnastics competition begins.

It will be qualification day for team finals, all-around finals and individual event finals, and the U.S. is expected to be well represented in everything.

Team coordinator Martha Karolyi speaks only of the importance of winning team gold; the defending world champions haven’t managed that since 1996 in Atlanta.

Their strong performance at the worlds in Japan a year ago, where American Jordyn Wieber also won the all-around title, has clearly caught the attention of the other contenders.

Chinese, Russian and Romanian coaches have been seen sneaking peeks at the Americans during training sessions, especially when the high-flying U.S. team works the vault.

Even though 16-year-old McKayla Maroney has seemed to suffer as many bumps and bruises as a football player, she is still able to soar and twist and point her toes (even if one is broken) and do her world championship-winning vaults.

Maroney, who fell so hard during a floor exercise warmup pass during U.S. nationals about six weeks ago that she broke her nose — even though she landed on her back — and who re-injured a toe she originally broke last May, will do only her gasp-inducing vaults today.

Four of the five members from full teams will compete on each of the four apparatus, and the top three scores will count toward qualification.

Raisman will be up first on the vault, followed by Gabrielle Douglas, defending world all-around champion Wieber and Maroney.

On uneven bars, Raisman will lead off again and Wieber, 15-year-old Kyla Ross and Douglas will be the rest of the rotation.

Ross will start off for the U.S. on balance beam and try to set a steady tone for Douglas, Wieber and Raisman, and Ross will do the same on floor exercise, where Douglas, Wieber and Raisman will finish up.

The U.S. women, who won team silver in Beijing, where Americans Nastia Liukin and Shawn Johnson won all-around gold and silver, will compete in the third of five subdivisions today.

Wieber and Douglas are considered co-favorites for the all-around title this time. Raisman could easily score high enough to qualify in the top 10 for all-around, but each country is allowed only two competitors in the 24-woman all-around finals and the eight-woman event finals.

Russia, China and surging Romania — in some order — are expected to push the Americans. And the Russians have a pair of 17-year-old all-around contenders as well.

Aliya Mustafina won the 2010 world championship before suffering a knee injury that required surgery and kept her from defending her title in 2011. Viktoria Komova finished second to Wieber in Tokyo and is the defending world champion on the uneven bars.