Eureka Teacher Cards, Emoticons, 36 Mailable Postcards (831915) Cards are an easy, inexpensive, and fun way for teachers to keep in touch with students Package of 36 identical cards Postcards are 4 x 6 inches and can be mailed with postcard postage Students enjoy the attention of a note from their teacher during summer or other breaks, or even during the school year Back of card looks like a standard postcard