Unless you want to face a social media ignorance charge such as the one against Pizza Hut's vice president of marketing communications Bob Kraut, you better think twice about asking your summer intern to tweet on behalf of your company.
Contrary to popular tweeting belief, corporate Twitter accounts are not for the sole purpose of announcing product promotions and discounts and fielding customer service inquiries. There is A LOT more to it than that. For many marketing communications executives not understanding the 'natural' factor on Twitter, it's so hard to be human, personable and engaging-- as opposed to being a feed hog with promotions, eating something (because it's the default tweet when you have nothing else to say), or talking about literally what you're doing at that moment. And so many digress to handing off this activity as similar to running errands and pushing paper all day long. What?!
Putting it into perspective
Say you're walking down the street alongside your trusty intern. They're jotting down notes of all their duties you delegate to them for the day. All of a sudden, an irate customer steps in front of you and demands an answer as to why their prescription drug is no longer on discount (You are a Walgreens marketer afterall). Stunned at what to say, you throw your intern at them and run off. Your intern is puzzled and the length it takes to reach you is as big as the organizational chart for your company. Would you really trust your intern to deliver a crisis communications response? By the time they find you for tweeting comment, the angered Walgreens customer has already posted a TwitPic of Walgreen's generic Ibuprofen with the caption "Don't be deceived. The Walgreens promotion ended weeks ago!" Unfortunately for you, they have 13,000 followers on Twitter and that pic has already received 1,200 views. An intern's "OMG, Walgreens is so not like that." Twitter response will not save you.
If you still want your intern to tweet, allow them to set up their own personal account that incorporates their passions, interests, and role outside of your company. The last thing you want is something mundane tweeted out on your company's feed and it just so happens that it's caused a slight stir and people want to know who said it and who they work for. Responsible and purposeful tweeting can be accomplished, and certainly among interns who are quick Twitter studies. But before you let the intern take the driver's seat for your company's Twitter, get your head examined. It's your deal-- not theirs.