I'm a high school physics teacher. Next year, I'll be teaching mathematics for middle school students so I was wondering if there's a curriculum based on recreational mathematics which not only present a sequence of puzzles and games but which also should have definite objectives. I hope there's such curricula because if not I'll have to make such one and it will take a really long time to author and test.
Actually there is a number of such books, though I wouldn't call it a "curriculum". I suggest you try the recent books by Ian Stewart, particularly Professor Stewart's Cabinet of Mathematical Curiosities (2008) and Professor Stewart's Hoard of Mathematical Treasures: Another Drawer from the Cabinet of Curiosities (2009).