What are the pros and cons to learning a foreign language?

The Pros
Two languages are better than one. It may sound backward, but learning a second language can give your child a firmer grasp on his first. Formulating foreign phrases requires the use of grammar skills, which allow him to better understand the rules of his native tongue. That double reinforcement leads to solid language and reading comprehension skills that can result in better grades across the board.
Master test-takers. Standardized exams have taken center stage in most American schools. Lucky for second language learners, two significant by-products of bilingualism are better cognitive skills and longer attention spans. Those skills combined contribute to great testing. A 2007 study by The College Board found that students with at least 4 years of a second language scored roughly 140 points higher in all three sections of the SAT. That's 420 points higher than their monolingual counterparts.
Increased employment options. Staffing agents read thousands of résumés per year and bilingual applicants are routinely at the top of the pile. According to Regis Canning, a staffing agent at NYC staffing firm Temp Agencies, seeing "fluent" on a résumé piques the interest of employers, and shows that a candidate "is smart and skilled with languages." Those perks make employers hire bilingual job seekers more often than not—even if language skills have nothing to do with the job.
Social circle expansion. Employers aren't the only ones who find more than one language irresistible. According to a 2004 poll, 97 percent of dating agencies asked applicants if they spoke a second language. These people-experts know that speaking a second language makes you look more worldly, intelligent and affable than English-only speakers. That social leg-up opens doors and opportunities that might otherwise be closed.
The Cons
Tutoring is expensive. Budget-savvy parents spend big bucks on language lessons because they're investing in bigger paychecks for their kids down the road—but the return on your investment may be smaller than you think. Contrary to popular belief, second-language fluency isn't a golden ticket to the next tax bracket. According to a 2007 study by University of Pennsylvania economists, the pay bump for learning a second language is small. The most common languages, Spanish and French, only earn speakers a 1 to 2 percent bump above grade.
School years yield a higher return. If you're looking for a way to make sure your kid rakes in the big bucks, skip the language lessons and invest that money in graduate school. For each year of extra schooling you give them, their pay check will increase 8 to 12 percent. By the time you're ready to retire, they'll have more spare bedrooms than their bilingual counterparts. Even those who speak German, Mandarin or Arabic—the most in demand languages—only earn about 4 percent above average.
The older you are, the harder it is. Let's face it—all most of us remember from 4 years of high school Spanish class are basic phrases like baño and gracias. However, that failure to retain foreign words may not be our fault; we may have missed our window of opportunity to learn languages easily. "Young children can acquire native-like fluency as easily as they learned to walk" says Leslie Lancry, CEO of Language Stars. Schools like Language Stars capitalize on this window and are able to teach children a new language simply through immersion. But according to Lancry and other experts, this window closes around age 10. After that, even years of tutoring may not make a language stick.
Your kid's schedule is full enough. The closer he gets to college, the busier his schedule gets. It's best to focus his energies on the subjects admissions officers care about. Jeff Fuller, Director of Student Recruitment at the University of Houston says "Most universities will look at the full depth and breadth of the students' course selection—especially comparing it to what the high school offers." Admissions officers won't ding a student for not taking classes their school doesn't offer, but they do expect you to take a healthy helping of AP and honors courses, and join sports and clubs. Adding language tutoring a few times a week can swamp your child and bring his overall performance down

Uhh well I know Russian as a second language, and the pros and cons are as follows: Pros: 1. its really handy if someone is talking cr*p about you,

2. Its just cool that you know a second language

3. you can teach people how to speak certain words
 
4. you can go to that country and not worry about the language difference

Cons: For me theres only one ( i sometimes confuse a russian word for a english word) 

but otherwise im very glad i know a second language

La noche pasada me desperte asustada

Amí y a mis amigos les gusta ir al parque. solíamos ir todo el tiempo, pero ahora no vamos tanto. mi familia y yo celebramos fiestas durante las vacaciones. en mi tiempo libre me gusta ir en monopatín y me gusta andar en bicicleta. here you go : )