What Goes Up by Katie Kennedy
200 teen scientists vie for two positions with NASA's Interworlds Agency.  The tests cover math, science, problem-solving...and a lot more.  Rosa Hayashi is an obvious choice.  Eddie Toivonen is not.
Then gravity flutters, which it definitely should not do.  Immediately after, alternate-dimension aliens show up, and they look human.  In fact, the alternate-dimension aliens look exactly like the astronauts who just left Earth, only these astronauts are carrying a very dangerous cargo.
What could possibly go wrong?
Part Charlie and the Chocolate Factory, part Ender's Game and part literary roller coaster.  Put it all together for a fast-moving, fun book with an intriguing premise and appealing characters who make nerdy the new cool.  Highly recommended!
Ages 12 to adult.  Some cussing, some kissing and some unbelievably corny knock-knock jokes.

 
 
