Younger son wants to hand in his brother's class 9 projects from last year

ICSE class 9 has a project in nearly every subject, and they count towards internal marks. My elder son did all of them last year, they came back with decent marks, and they are sitting in a cupboard in very good condition. The younger one's plan is to 'update' them. Same topics, new cover page, his own handwriting if pressed. He points out that the teachers have changed. I point out that it's copying. He says it's recycling, and that we keep telling him to be environmentally conscious. He's not submitting them, obviously. But is it reasonable to let him use them as a reference, or does that end up being the same thing in practice?