GLEN ROCK, N.J.  In a class full of aspiring engineers, the big bad wolf had to do more than just huff and puff to blow down the three little pigs’ house.

To start, he needed to get past a voice-activated security gate, find a hidden door and negotiate a few other traps in a house that a pair of kindergartners here imagined for the pigs  and then pieced together from index cards, paper cups, wood sticks and pipe cleaners.

“Excellent engineering,” their teacher, Mary Morrow, told them one day early this month.

All 300 students at Clara E. Coleman Elementary School are learning the A B C’s of engineering this year, even those who cannot yet spell e-n-g-i-n-e-e-r-i-n-g. The high-performing Glen Rock school district, about 22 miles northwest of Manhattan, now teaches 10 to 15 hours of engineering each year to every student in kindergarten through fifth grade, as part of a $100,000 redesign of the science curriculum.

Spurred by growing concerns that American students lack the skills to compete in a global economy, school districts nationwide are packing engineering lessons into already crowded schedules for even the youngest students, giving priority to a subject that was once left to after-school robotics clubs and summer camps, or else waited until college.