I personally wouldn't change. I'd just adhere his rectangle projects and papers to 12x12 pages and put them into the book that way. I'm doing a Cathy Zielske-style school album for my daugher and it's 12x12 3ing album. All of her papers/projects and the like will go in a pocket page designated for each year of school. All of my other scrapbooks are 8x8, but the school ones will be 12x12 so I can incorporate the larger memoribilia pieces. When my daughter leaves home she can take her school books with her and I can keep all the others.
Getting a bit off topic there, but no, I wouldn't switch.