It is as if something in the rarefied air of Whitehall prevents each new administration from remembering the follies of its predecessors, so that the same piece of nonsense emerges again and again.
Serious educators have long realised that compulsory homework serves no bankable educational purpose. It came into being in imitation of the public schools, which required pupils to prepare the next day's Latin or Greek construe.
Nowadays it merely serves to restrict the time in which children can play when they come home from school. Adults tend to see this as a good thing, because they don't understand that play is the proper activity of children and contributes far more to their mental and intellectual health than study does.
Compulsory schooling tends to fail because it refuses to acknowledge that valuable learning only happens when a person, adult or child, freely chooses his study and willingly commits himself to it.
You cannot legislate for that commitment, and if a child has not made it when you impose homework on him or her all the signing of contracts and minatory finger-wagging in the world will not make the exercise worthwhile.