I am returning to the OER project after a 2 year hiatus. I previously taught Big History for 3 years and loved it. My district chose to drop BHP altogether. This year, I have been assigned Modern World History, a class I have not taught in over 10 years. The textbook my district now uses is significantly different than the previous one. I always liked the Big History format, and supplied materials. I am hoping to incorporate the OER World History curriculum into my lesson plans this year. Would it be more effective to merge the two curriculum guides into one, or should I go with OER and use my district's text (McGraw Hill ConnectED) as a supplement (or vice versa)?