I am not sure I agree with this study. It sounds like they are trying to place blame for the boys low score solely on divorce. I know that many boys are lazy and they do not always want to learn. Getting them to read and better educate themselves is a must. Giving them an excuse is not helping the problem.
Schools 'set sights too low'
Teachers are deliberately setting low goals to stop primary school pupils failing and some principals are hiding poor academic results from boards of trustees, a government report reveals. Ref. Source 7