Board Thread:Episode Discussions/@comment-22498334-20160718022822

For Itachi's Character page I noticed that some of the filler? (450-IDK-what) episodes of Naruto Shippuden were cited as source material. Is the information provided by these sources canon or not? Just wondering, as said information would help me in creating a naruto timeline. On a separate but relevant note; I could not help but notice that Choiji and Shikamaru appeared in the same classroom as Sasuke on Sasuke's first day at the Academy, and they were also in the same classroom as Sasuke when Naruto (who failed three times prior and should be two classes behind them) and the other members of the academy graduated to Genin rank. Does this mean that for some reason everyone in Sasuke's academy year were held back for three years or however many years there are between Sasuke entering the academy and the start of the manga?  