I need to know how many squares I need to piece together to cover a queen size bed. Im interested in just the top of the bed only because I want to add ruffles to overlap the bed. Thanks.
If you want to cover just the top of the mattress, without ANY of the pieced part hanging over the side, the dimensions of a standard queen size mattress are 60" x 80". You should measure the bed it's going on, though, because it might be different. For a 60 x 80 top, you'll need 300 squares - 15 across and 20 down.
If it is made entirely of 4" FINISHED squares, you'll need to cut the squares 4 1/2" (because you'll lose 1/4" on each side in the seam), so be sure you have enough fabric.
If you're CUTTING the squares 4" (for a finished 3 1/2" square), you'll need 391 squares, and it will be 17 across and 23 down.