A friend from church gave me great advice on cards and it is too good to not pass along to you!
You can make 300 cards for under 10 cents a piece.
This is what you need from, yes, Walmart. If you don't like shopping there why not make a special trip there very, very early in the morning. You then will pretty much have the entire store to yourself.
In the office supply section buy a package of white card stock (150 sheets). I just bought some in August or September and it cost around $8. In that same section you should see "Invitation Envelopes" that are about 4 3/8" X 5 3/4". In our store they are under $5 for 50 envelopes.
After visiting the office supply section, go to the party/card section where they probably have scrapbooking supplies. Again if your Wal-mart is like most you will be able to buy a bundle pack of scrapbooking papers and cutouts for under $10, I just bought one for $7. In the case that you already have pretty papers and things at home, save some money and use what you have first.
1. Cut a 8 1/2" X 11" piece of card stock in half so that the 2 halves measures 5 1/2" X 8 1/2". Cut a few more, I'll explain later.
2. Fold the cards so that they are 5 1/2" X 4 1/4", use a teaspoon or a ruler to rub the fold flat.
3. Think of or borrow a design for the front of a cover and duplicate it for a few more cards. If you do a few each time you need a card, you will quickly accumulate a nice assortment.
There is 1 card above that was decorated by a 7 year old with foamy stickers. Kids LOVE making cards too, so this is a fun project for the family.
NOTES: The cosmos flower in the first/second picture is a cut out dye that I used for a sunflower project. The 3rd card was made from a $7 bundle pack that includes 40 patterned 12x12 papers and 437 cutouts. I use Elmers Glue for the cards because people do not usually keep cards for long. I added glitter to the name in the 3rd card as well.