Want to send a nice message quickly easily and inexpensively? Just jot down a quick note along with the address add a stamp and drop one of these colorful postcards in the mail!Teacher Created Resources Thank You Postcard from Susan Winget for all grades is designed to send a nice message quickly easily and inexpensively. Postcard measuring 4 x 6 is a perfect thank you note and sold as 30 per pack. Size: 4 (H) x 6 (W). Age group and grade: All grades. Occasion: Thank you. Want to send a nice message quickly easily and inexpensively. Just jot down a quick note along with the address add a stamp and drop one of these colorful postcards in the mail. 30 postcards per pack. Sold as 30/Pack.