 CTW's early studies with the distractor found that children learned more when they watched the program carefully, or when they participated by singing or talking along. In re-tests four weeks later, it found that children retained most of what they learned. After the first three weeks, or 15 episodes, viewers and non-viewers were compared; few differences in learning were found. When both groups were tested after six weeks more differences began to appear, with viewers scoring higher than non-viewers. A two-season CTW study published in 1995 found a "significant increase" in difficulty in remembering the letter and number of the day. Based on the multiple-intelligence theory, producers began to cluster Sesame Street's short films, animations, and inserts around a single topic rather than sprinkling several topics throughout a single episode.
