Watch it, kid, or you might grow up to be president.

As well all tot up our final grades for our students at the end of the school year, we teachers (and parents) often despair of those underachievers who scrape along with the Ds and C-minuses and seem not to care.

Well, now we've got a new threat that could really scare them: If you don't get your grades up, you might end up being the president.
As Ann Sanner of the AP writes, Kennedy was almost expelled, Truman struggled with punctuation, and Eisenhower could be rude:

Lyndon Johnson got a D in his third-grade grammar class. John Kennedy scored a 55 in eighth-grade Latin. George H.W. Bush's high school transcript shows marks in the 60s and 70s for many classes.

"We want to believe that there is a class of people who emerge early on as heirs to the throne, so to speak, but that's not the case," said Timothy Walch, director of the Herbert Hoover Presidential Library.

The youthful days of presidents are the subject of "School House to White House: The Education of the Presidents," an exhibit at the National Archives.

Through their own accounts, the cursive script of their early writings, report cards, playbills and photographs, the exhibit highlights just how normal most of them were in their youth.

Most attended public schools where math, reading and science were the core of their education. Some were also graded on citizenship and physical training. Franklin Roosevelt, Kennedy and Bush attended prestigious boarding schools.

Outside the classroom, they were athletes and performers.

Johnson, Roosevelt and Richard Nixon showed their talent in school plays. Bill Clinton was the drum major of his high school marching band. Gerald R. Ford captained his high school football team.

Dwight Eisenhower's competitive streak ranged from the class spelling bee to baseball diamonds and football fields. Spelling was his favorite subject in grammar school. "Either because the contest aroused my competitive instincts or because I had learned that a single letter could make a vast difference in the meaning of a word," he wrote.

Each had his own vulnerability.

Jimmy Carter was shy, but a high school teacher encouraged him to join the debate team. Roosevelt wrote home from boarding school almost every day and spared no details. In one letter, the father of the New Deal revealed he had gained several pounds and received no "blackmarks." He also asked his family to send grapes or other fruit.

Some were known for their behavior — good and bad.

Herbert Hoover's teacher described the 10-year-old as "a real boy, loved play, but his lessons came first." She said she never had to tell him to redo work or punish him for not completing it.

Kennedy's headmaster once said the teen had a "clever, individualist mind," though he might have called him a "Mucker," too. Kennedy and several of his friends from boarding school formed a group called the "Muckers," named after the headmaster's term for boys who failed to meet the school's standards.

He was nearly expelled during his senior year for his antics as a Mucker at Choate School in Connecticut. He broke up the group and was allowed to stay.

In a letter, Kennedy's father once told him to step up his efforts in class. Instead of working hard in all subjects, Kennedy mainly focused on his favorites — English and history.

"It is very difficult to make up fundamentals that you have neglected when you were very young, and that is why I am urging you to do the best you can," Joseph Kennedy wrote. "I am not expecting too much, and I will not be disappointed if you don't turn out to be a real genius, but I think you can be a really worthwhile citizen with good judgment and understanding."

Punctuality was a problem for Johnson, whose ninth-grade report card shows that in two months he was tardy eight times.

Eisenhower could have skipped a grade if it weren't for his bad manners. "My conduct was not the equal of my reading ability," he once wrote.

Some of their junior high school writings show glimpses of the leaders they would become.

Nixon contemplated a career in politics even as eighth-grader.

"I would like to study law and enter politics for an occupation so that I might be of some good to the people," he wrote in a class autobiography.

Harry Truman's writings show his idealism but not a knack for appropriate punctuation. "A true heart a strong mind and a great deal of courage and I think a man will get through the world," he wrote in an English theme book in the archives' collection, a reproduction of which is on display until Jan 1, 2008.

In a classroom filled with eager students, picking out a future commander in chief is impossible, Walch said. "There's no way that you can identify some young man in the fifth grade and say he'll turn out to be president."

I would love to see this exhibit, but having been an underachiever myself in school, I would hate to think of MY report card as being on public view. This just goes to show that it's never too late to turn your life around-- or, if you're a curmudgeon, that some slacker kids eventually DO get punished with one of the hardest jobs in the world. So work now, kids, or risk being worked into premature wrinkles later.