Begin with a warmup by naming the continents, then asking students to name as many countries as they can (ask them which continent the country is in before writing it on the board). This is usually a pretty engaging activity, and can be adjusted to various comprehension levels (for higher levels, maybe also ask what language they speak there, for lower levels you can accept answers in Japanese and tell them the name in English). Once you have a good variety of countries (I try for at least 2 from each continent) then you can hand out the worksheets.
For activity 1, you can let them use the countries already written on the board. If you want to make it more challenging, maybe ask for some that are NOT on the board. Activity 2 can be adjusted as needed. Simply ask them to write their three favorite countries, but they cannot say "Japan" as one of their answers. Again, to make it more challenging you can throw languages into the mix. On the handout I also excluded the U.S.A. because that's where I'm from, pushing for students to get more creative with their answers.
After that, break them into groups of 3-4 and have them decide on a country they all want to go to, and why. Then they can do activity 3 as a group together, deciding what to pack. I wrote down some examples just to give ideas (a coat if they're visiting a country with a cold climate, sunblock if the country is very sunny, etc.) Try for at least 3 items they'll pack.
The last activity is the presentation. This lesson was designed as a group project, but you can adjust as needed. It can either be graded or just a practice presentation. If you want to do the presentation as a group, I ask each of them to say at least one sentence from the presentation template.
Overall, the lesson takes about 2.5-3 classes to finish. In a 45 minute class period, the first class will probably include activity 1 and starting activity 2 (naming 3 countries). The second class should be group work, finishing activity 2 and going through explaining activity 4 (with time at the end for them to fill in blanks and practice). The third class, give then time to prepare at first, then have them present. Again, this can be either graded or just for practice, your choice. I taught this lesson for high school students of all 3 grade levels, and can be adjusted to make it easier or harder, depending on what your students need.
(Disclaimer: this lesson was pretty experimental, trying to mix together a fun warm-up activity, group work, and building up to a presentation. By all means, make any changes you think are necessary. I hope you find this lesson to your liking!)