It is Frugal Friday at http://www.Biblicalwomanhoodonline.com/blog.htm. My frugal tip is to buy basic/classic clothes that do not go out of style. Layer them to make your short sleeve shirts wear into the winter. For bottoms buy denim, khaki/olive, white, and black.
For boys: Layer short sleeve tees,polos and button front shirts over long sleeve tees and even sweat shirts. Or wear them under long sleeve button front shirts. Wear hoodies under jackets to add warmth.
For girls: Opt to buy skirts over dresses. Choose colors and the weight of fabric that can be worn both in the summer and winter just by changing tops. You can also get many more outfits with a skirt by changing the tops.
A white button down can be worn with a skirt left untucked with a belt, with jeans for a casual look, with pants, with a formal skirt, under a sleeveless sweater, under a cardigan, sweater, or blazer. It will look casual to dressy depending on the pieces you put it with and the accessories.
Buy basic loafers, tennis shoes and sandals for boys. Girls need a white shoe in the summer and black in the winter plus a pair of tennis shoes and sandals. For me, I buy black, ivory, sandals, and tennis shoes. Of course I add pieces to this (like these http://southernseven.blogspot.com/2008/02/new-clothes.html) but if you have the basics you don't NEED anything else.