My history curriculum is secular SOTW set out the way TWTM says to do it, 3 days a week. (I did take SOTW slightly out of order, mostly b/c their are 42 chapters, so I had to combine some things to get it down to less than 43 weeks.) I have 4 levels planned, and I am almost halfway done with the first two for SOTW 1. The first level has plenty of picture books. Some of these are harder to obtain or more expensive if you don't use the library, so the second level is for the same age group, etc., but all books are available at Amazon.com and I tried to make sure that they were affordable. Every book recommended has been read and includes notes about anything that may need editing. There are notebooking pages, usually 2 per week. And maps and activities, of course. There are timeline activities as part of the notebooking pages and I am planning free instructions for a large timeline.