Will.i.am -- I Build My Ugly Cars ... To Teach Kids Science

Will.i.am has a damn good reason for building his hideous expensive cars -- like his new $900,000 Dick-Tracy-from-the-future jalopy -- telling TMZ, it's ALL FOR THE CHILDREN ... in order to teach them science ... or whatever.

We asked Will about the new ride -- recently spotted around town -- and he tells us, "I built the car for a project that I'm doing in inner cities. I round up a whole bunch of people who are qualified to teach kids science, technology, engineering, and mathematics. And through the course, they build vehicles."

He adds, "So I have to build different types of vehicles that can be used in a tutorial. That's the only reason that I build cars ... to invest in tools so kids today can have the skills for tomorrow."

Too bad it's impossible to build a car for less than $900,000.