Tuesday is Election Day. After months of campaigns, debates and political ads, it’s time for Americans to decide who should be the next president. Will voters reelect President Barack Obama, the Democrat? Or will they decide the United States needs new leadership and vote in former Massachusetts Governor Mitt Romney, the Republican?

Often, we don’t know who has won a presidential election until very late at night. Sometimes it can take days — or even weeks — to know who the winner is. We’re not saying you should often stay up past bedtime on a school night, but you could tell your parents that you want to stay up because elections are an important part of U.S. history.

If that works, you’ll want to have this KidsPost section with you as election results come in. It’s part art project, part math worksheet, part history and — we hope — all fun.

Here are some things you need to know for the big day on Tuesday:

→Poll closing times: You can’t get any results until the polls (where people vote) close. Polls close at different times in different parts of the country. The first polls close at 6 p.m. in Kentucky and parts of Indiana. The last polls close at 1 a.m. Eastern time in Alaska. (And no, we are definitely not suggesting you stay up that late.)

→Red states and blue states: Here’s the art project part of Election Day. You’ll need markers, crayons or colored pencils in red and blue and a map of the United States to color in that you can download from here. The map of the United States with this story has most states colored either red or blue. Red states are the ones that Mitt Romney is expected to win; the blue ones are states that President Obama is expected to win. As you watch the election results, you can color states that Obama wins in blue and states that Romney wins in red. If Romney wins a state that Obama is expected to win, that could be important. Some states are yellow because both candidates seem to be doing well there. Who actually wins those eight states could be very important, too.

→ Popular vote: This is the total number of votes cast across the country. You might think that whoever wins the most votes becomes the president. That’s how it works most, but not all, of the time. Four times in our history — in 1824, 1876, 1888 and 2000 — the person who won the popular vote didn't become president. So now you’re wondering how that can happen, right? Keep reading . . .

Electoral votes: When the American people vote, they are actually choosing people for something called the Electoral College. It is the Electoral College that actually chooses the president. Each state gets a number of electoral votes based on the state’s population. (Maryland has 10; Virginia gets 13 and Washington — which isn’t a state but still gets electors — has three.) That’s why states with a lot of electoral votes are important in the election. Also, in most states electoral votes are “winner take all” — so, for example, if Mitt Romney wins Florida by just one vote, he still gets all 29 of its electoral votes. There are 538 electoral votes up for grabs in Tuesday's election. Whichever candidate gets 270 of them becomes the president. Download a tally sheet to help you add up the electoral votes — that’s the math worksheet part.

→ See how kids get involved! Tuesday’s KidsPost will be devoted to kids — just like you — who really care about the election. We’ll have letters from sixth-graders about political advertising and we’ll show off some Silver Spring girls who got political for Halloween. Even the weather art will have a special “get out the vote” theme!

→More online: Take a quiz to see if you could become president.

★Read about President Obama and Mitt Romney.

★Understand how political advertising works.

★Discover why presidential debates matter.

DOWNLOAD: Tally up electoral votes

DOWNLOAD: An electoral map to color in

Tracy Grant