Ho much money can I carry before the IRS is interested?

So i'm a teenager working, doing odd jobs like washing cars and painting decks. I was wondering how much in paper money can you carry on you without the IRS wanting you to pay tax? If that didn't make since at all, i talking like how much before they blame you of tax evasion. Because i know they stopped making the five hundred dollar bill because it was far too easy to carry large amounts of money.