Today I'd also found a link to the Cuisenaire Rods manipulative on the NRich site, which is absolutely fantastic. I remember discovering a dusty old box of rods in the resource cupboard during my NQT year, digging them out and then not really doing anything relevant with them because I didn't have a) the time or b) the experience to work out how to use them without just confusing the pupils more. I'd always been determined to go back and check them out properly though, particularly with the links to the work I've been doing with algebra tiles.