My monkeyman is only four and so our math curriculum is pretty simple.  Math manipulatives are expensive and I have some tanagram sets, cuisinaire rods, and also a box of crayons.  A box of crayons... you say?  They are excellent for teaching amath.  Friend who used to be a teacher gave them to us.  They are many many mixed up sets.  I use them for math this way- we start with a basic worksheet- either one from a book purchased at the store or one I make on my own since our workbook is mysteriously missing.  We are doing addition and subtraction and practicing writing and identifyoing numbers.  I have one piece of paper with a fold in the middle.  Monkey man must read the problem aloud and then build it using several crayons of the same color.  So for the problem 3 plus 5 he puts 3 crayons above the fold, puts the plus sign in the middle, and five crayons below the fold.  Then he counts the total number and identifies the correct answer from a pile of number cards.  He can pick up the number card and look at it while he writes the correct answer on the problem sheet.  It may sound like a complicated way to get the work done but I am hoping that the one to one correspondence and the kinesthetic aspects help him to internalize the process.