We’ve said it before, and we’ll say it again: Big boobs, itty bitties, in-betweenies -- they’re all beautiful! But when it comes to getting a bra, it’s so important to have the perfect fit. We want to keep you, er, abreast of what to look for when bra buying.

Bare Necessity?
Wondering if you even need a bra at all? It’s a personal decision, but maybe your breasts are beginning to bud, and you’re thinking of trying your first bra. It nicely covers nipples, if nothing else. Even if you already wear a bra, you might be bopping around in the wrong size.

Not an 8-ounce Cup!
So, what’s your bra size? Here’s the formula:

1. Use a measuring tape to determine the number of inches around your chest, just below your breasts. Add 5 inches if it is an odd number; add 4 inches if it is an even number. This is your bra measurement.

2. For cup size, move the tape up to measure your chest around the fullest part of your breasts.

     If the two numbers are the same, you need an AA cup.
     If the two numbers differ by 1 inch, you need an A cup.
     If the two numbers differ by 2 inches, you need a B cup.
     If the two numbers differ by 3 inches, you need a C cup.
     If the two numbers differ by 4 inches, you need a D cup.
     If the two numbers differ by 5 inches, you need a DD cup.

So, pretend your first measurement, below your breasts, is 28 inches. Adding 4 inches makes 32. Say your second measurement, across your breasts, is 34 inches. The difference between the two numbers (in this case, 32 and 34) is 2 inches, so you’d need a B cup. Your bra size would be 32B.

The Ultimate Breast Test
Spend time in the dressing room trying on a variety of bras. Once you find one you like, jump around in front of the mirror, then lean forward. Boobs still secure? Good. Now see how it looks under your shirt. No weird bulges or traces of lace? Remember to adjust the straps and the hooks on the back to get the best fit. Not so bad, eh?

What’s not to love about a girl who’s out to make major world changes? We’ve rounded up three of our favorite do-gooder gals.…

Hannah Teter: Couldn’t be Sweeter
Competitive snowboarder Hannah Teter, 22, won gold in the 2006 Winter Olympics, but she didn’t let that medal muddle her head. Instead, she put her newfound clout to good use. “I’ve always wanted to help out in the world,” she says. “I now have the opportunity to pursue this dream.” So she decided to “sweeten the world one bottle at a time” with maple syrup from her home state of Vermont. Huh?

No, Hannah doesn’t think the Earth is flat as a pancake. But all profits from sales of her Hannah’s Gold Maple Syrup help poor children in the African community of Kirindon, Kenya. “I got to see the difference between clean water and dirty, disease-infested water that the kids were drinking previous to their rain water catchment system,” says Hannah of her trek to Kirindon. So far, she’s raised over half her goal of $100,000. Sticky sweet!

Ayna Agarwal: Doggone Do-gooder
During a trip last year to visit family in New Dehli, Ayna Agarwal, 16, was appalled to see helpless, homeless dogs wandering the streets. So she started Stop Pet Overpopulation Together Globally (SPOTGlobally), an organization to prevent animal overpopulation, starvation and cruelty.

SPOTGlobally has project sites in several locations worldwide: South Africa, Thailand, Nepal, Italy, Philippines, Mexico, Lebanon, Dominican Republic, Columbia and India. At the Friendicoes shelter in New Dehli, over 200 pets are cared for at any given time, but sadly, most have little hope of being adopted. Ayna’s program provides medications and surgical supplies. How does it benefit the world as a whole? Stray pets on the streets can lead to the spread of diseases -- such as rabies, a great endemic in India.

Amira Mortenson: Making Changes out of Change
What’d you drop on your last mocha latte? Three bucks? Five? A single cent in Pakistan can buy a pencil, and a dollar educates a girl for a month, says 13-year-old Amira Mortenson as she travels the world with her father promoting Pennies for Peace. Pennies for Peace inspires kids to collect spare change to support causes, such as building schools in Pakistan and Afghanistan.

Meanwhile, Amira’s dad has received death threats and even been kidnapped, mainly because he wants to help educate girls in volatile countries, as documented in his book, Three Cups of Tea. Amira continues to follow her father and her heart, influencing kids to care and share. “Our generation should be totally dedicated to peace, not war,” says Amira, “and we should make sure every kid in the world can go to school.”

Say you just ran into your crush or your best guy friend. He’s staring at his sneakers, stumbling over his words and…are those sweat stains under his arms? You’re not alone if you walk away scratching your head and thinking, “Huh? Wha…?” But we’ve got the straight-up facts, right here.

Fact: Boys are just as intimidated by you as you are by them.
Boys tend to get embarrassed around girls, but why? Well, on average, boys mature at a later age than girls. So guys don’t always know how to act in a way that’s, um, composed. And because of this lack of maturity, they have a thing for making fun of each other. So if you’re talking to your crush, you can bet he’s probably thinking, “Sheesh, I hope my friends don’t see me hanging out with this girl! They’ll bust on me, for sure.”

Fact: They have a harder time talking about their feelings.
Girls are way better at expressing their emotions than boys are. Some of this has to do with hormonal differences, but part of it has to do with societal expectations. Guys are “supposed” to be rock-solid. So do boys have feelings? Yes, absolutely! It’s just that they have a more difficult time putting them into words and spitting them out.

Fact: Boys don’t menstruate, but they have mood swings!
Mood swings aren’t just about having your period. They’re a part of puberty for girls and boys. The difference is that while girls tend to get sad and sometimes weepy, boys lean more toward anger and frustration. Is he grumpy? Don’t take it personally.

Fact: Their voices go whacky right around when they turn 15.
You used to call your guy friend on the phone and couldn’t tell if he answered or if it was his sister, right? And then one day, he picks up and you think it’s his dad! What the heck? Before that, you might have noticed that his voice was squeaking and cracking when he got called on in class. That’s because his larynx, or voice box, has been growing larger and thicker. This happens to girls, too, but your voice only deepens by a few barely audible tones. This may come with a whisker on his chin…

Fact: Boys’ sweat gets smellier as they get older.
Again, puberty is the culprit. Those pesky hormonal changes cause sweat and body odor. And, yes, girls have this problem, too. But girls tend to have better personal hygiene, which means bathing regularly and using deodorant. So he comes off the field after practice, and he’s all dirty and dripping with stink. Ick. But hang in there. As he catches up with you in maturity, he’ll care about how he smells. Because he won’t worry anymore about what his friends think when he’s talking to a girl.

Hey, it’s not that girls don’t want to play sports. But a recent Women’s Sports Foundation study shows that many girls still aren’t getting a fair shake in the athletic arena. That’s out of bounds! Especially when it’s been shown (and this research confirms) that kids who participate in sports are healthier and happier, get better grades and have more family involvement.

The Gender Gap
Yep, there’s a gender gap in physical activity between girls and boys. In general, boys are exposed to more athletic opportunities than girls. In the United States, a staggering 68 percent of girls living in rural communities have no physical education classes at all in 11^th and 12^th grades. For urban girls in the same grades, a whopping 84 percent report no phys ed!

An Uneven Score
Not all girls are losing out. In some communities -- usually suburban -- girls and boys get equal playtime. But girls from urban areas, which are often economically challenged and have fewer school resources, are the ones largely left out of the game. One in four 9^th- to 12^th-grade urban girls has never participated in an organized school team sport.

Nothin’ About Biology
OK, so some people might think boys are just naturally more interested than girls in sports. Wrong! The study finds that girls’ and boys’ differences have more to do with opportunity and encouragement. In fact, boys tend to exaggerate their enthusiasm for sports (maybe they think it’s expected of them). Forty-two percent of third- to eighth-grade boys said “sports are a big part of who they are” even though they weren’t athletes!

Girls Got Boys Beat
While girls are less athletically involved overall, they participate in a way wider array of various activities than the boys do. The boys tend to stick to the traditional old-school stuff, but the girls do that and then some. They explore recreational activities, like double Dutch, dance, cheerleading and volleyball, that break away from the strictly conventional.

Late in the Game
Girls generally get involved in sports at a later age than the boys. On average, boys join the team at around 6 years of age, and girls jump in when they’re about 7-years-old. Girls also drop out of the game a lot earlier and in greater numbers than boys, and some researchers blame this on the late start setting girls up for failure. This usually happens during the middle school years, but perhaps this will encourage you to stay in the game: Girls who participate in a team sport are more content with their lives than girls who don’t play sports.

Make the Team
Researchers observed that the positive social, health and educational (triple threat!) benefits of being athletic were most apparent in girls and boys right around sixth- through eighth-grades. So, what’s a girl to do if her school doesn’t offer any sports opps? Well, the report’s title says it all: Get Out and Play! Round up your crew, and start a dance club, plot a bike route or kick off a soccer game in the park. Better yet, get the gals to rally your rec center or school officials about getting girls active in organized athletics. There’s no way you can’t win!