It also rhymes with common parenting folk wisdom that having "the wrong friends" is detrimental to grades.
>the challenge isn't explaining, it's to get the students to care.
This.
The reason not one student learned French in my four years of mandatory French classes is that we didn't want to know french. We didn't know any french people. We didn't care about french songs or movies.
OTOH, when telenovelas became a local fad, every girl had a clique of Spanish speaking 13 year olds.
The actual problem in that case is: How do you teach french/philosophy/whatever to a class full of kids who don't want to learn that stuff? Maybe they want to pass exams and get grades. Maybe you can rejigger discipline mechanisms to motivate them... but that is never going to get you to good.