I know that there are several travel lesson plans on here, but I hadn't come across a 'post card' lesson plan persay. This lesson can be used by itself (as a filler) or as an extension to another travel lesson if need be.
I used this with my 2nd year middle school students (boys and girls) and overall it has gone very well. It will take about two classes; one class to write the post card and the second class for the students to finish up writing/and present their travels.
I made sure to point out that the students should write their letters first then draw their pictures second (many students spent the entire class period working on their post card picture rather than their letter if I didn't do this). Also, while I did get a lot of scripted letters (they used the power point example--but changed the necessary information) several students became very creative. Make sure to let the students know that they can be creative with their letters!
Another side note: I did borrow travel books (in Korean) from my school library, and I found that the students really enjoyed looking through them and picking a place to visit. I also threw in the mix several of my lonely planet travel books and National Geographic Travel Magazines. While the English books didn't go over so well, the students did use the pictures in them as guides.
Good Luck!