Complex sentence: On April 17,2011, CBS 60 Minutes aired a convincing investigative piece on CAI and Mortenson, determining that CAI spent more money promoting Mortenson's books than it did on schools, and that Mortenson's alleged accomplishments, though substantial, were greatly exaggerated.
Split into simpler sentences: On April 17,2011, CBS 60 Minutes aired an investigative story on CAI and Mortenson. The story alleges that CAI spent more money promoting Mortenson's books than it did on schools, and that Mortenson's accomplishments, though substantial, may have been greatly exaggerated.