This was a little difficult for my ES 4年 students but they did enjoy it. The PPT asks what time it is in other countries, if it is noon in Japan.
You'll have to explain time difference (Japanese: jisa) first. You can use the picture at the beginning of the PPT to help, and the homeroom teacher. It might take time, but it's a valuable concept to know. They study it in 4年 I think.
Next, you'll have to explain the premise that it is noon in Japan. Just keep reminding them during the PPT.