Iron Thunder by Avi

Another Nutmeg nominee, Iron Thunder is a historical fiction novel based on the battle between the Monitor and the Merrimac. . Tom Carroll is but 13 years old in 1862 when his mother asks him to find a job to help put food on the table. And what a job he finds - errand boy for Captain John Ericsson - inventor of the first ironclad ship. Will something made of iron float? Will it be capable of fighting of the rebel "sea monster," known as the Merrimac. Plenty of action including Tom being wooed by a rebel spy.