Complex sentence: The Catholic church encouraged a boycott of the new schools so, though by 1883 3,885 secular schools had opened across the country, attendance in private Catholic schools had risen from 13 percent to over 60 percent.
Split into simpler sentences: The Catholic church encouraged a boycott of the new schools. By 1883, although 3,885 secular schools had opened across the country, attendance in private Catholic schools had actually risen from 13 percent to over 60 percent.