That tweak for four corners sounds great, I'll definitely use that idea if I ever find myself teaching in a primary school again!
I found the evolution game great for 3/4 (5 at a push) too (can find templates etc in loads of the threads in the planning sections).
For older kids, I tend to stick with surveys and that sort of thing, but it can be a mission to motivate them to get off their seats. I've had great success with an activity called 'zombie virus survey' though; the Ss complete a survey of their classmates and sit down when they've finished. When everyone has finished, ask them to stand up and randomly select Ss who have the 'zombie virus'; these students sit down and anyone who surveyed them is also out. Last Ss standing are the winners. The tricky part is choosing the right number of zombies to choose for your particular class size, but trial and error is your friend
Running dictations can also be quite effective for the older kids, but mileage may vary depending on your students' energy and English levels ...
