I just heard the following story (in the name of one of Rabbi Paysach Krohn‘s many books).
The Lubavitcher Rebbe once suggested teenage boys begin with Berachos instead of Seder Nezikin. Berachos is the beginning of Shas. And saying Shema is more practical than goring oxen.
But Rabbi Moshe Feinstein was strongly opposed, immediately calling a meeting to kill the change. He explained, that during summer vacation the youth will wake past the Zeman, and will gather there is no connection between what they learn in Yeshiva and their own, personal lives. Keeping halacha is for older rabbis, not for them.
Whereas, learning Nezikin will teach them something practical they can readily observe; don’t touch someone else’s belongings!