Você é um menino.
Would you really say to a boy "você é um menino"? I thought that "você" is the polite form, used with people aged 18 or over, and "tu" would be used with kids. Am I wrong?
That doesnt happen in Brazil. Just take a look: http://duolingo.com/#/comment/78116?from_skill=cc59353ddf030721d7721c3c9c8cdf04