Killer rocks from outer space: asteroids, comets, and meteorites

 Koppes, Steven N.;

Minneapolis, MN : : Lerner Publications , 2004

Jonas Salk: conquering polio

 McPherson, Stephanie Sammartino; Salk, Darrell;

Minneapolis : : Lerner Publications , 2002

Plate tectonics

 Johnson, Rebecca L.;

Minneapolis : : Lerner Publications , 2006

How congress works :a look at the legislative branch / Ruth Tenzer Feldman

 Feldman, Ruth Tenzer;

Minneapolis : Lerner Publications , 2004