Teaching a combo 5th/6th class again this year. Last year I utilized a largely 5th grade focus. This year I will need to use 6th and several elements of 5th in Math and heritage studies and possibly science. BJU 5th/6th English both corresponde beautifully in terms of lessons integration and there is little I need to do to keep students on the same topic and have expectations on grade levels, but other subjects don't dovetail so seemlessly. Math, science and history have very different topics and approaches. Any ideas? We are using the older editions for all these subjects if that helps.