The difficulty of adapting tasks to Japanese Jr. High Schools without destroying them

I teach a graduate school seminar on Task Based Language Learning. For the seminar we have read the Willis book, a Framework for Task Based Learning, and a chapter from the new Paul Nation book, Teaching ESL/EFL Listening and Speaking which gives a lot of good ideas for tasks. The class consists of 3 Japanese graduate students and a researcher from Pakistan. Next week, they will go to a junior high school (JHS) and teach a lesson that is supposed to feature a language learning task. Our goal (or at least the goal that I imposed) is the following:

"Design a task supported lesson that will encourage communication and interaction among junior high school students to reinforce their understanding of how to use the language they have studied up to that point."

Last week the student-teachers designed a lesson plan which consisted of a jumbling task, where the JHS kids would have to order a story, and then a writing task where the JHS kids would have to write the ending of the story. The problem was that the story was too complex for the JHS kids and the writing task was too long. We went to the JHS last Thursday to present the plan to the teacher and she rightly pointed out that it would take about 3 classes to do such a task. On the way back to the university from the JHS I reiterated to the student-teachers that they needed to drastically reduce the content.

Tonight I got the new lesson plan from the student-teachers and I was shocked. The lesson is only task by name. It changed to a typical JHS lesson. To make a long story short, they plan to read half a story to the JHS kids in English, have them write the ending of the story in Japanese, and then change the story to English. Last the kids will read their English story to each other. What is worse is that the JHS where they will teach did a similar lesson which the student-teachers observed. The lesson was actually pretty good. What bothers me is that the graduate students' lesson is like a bad imitation. If they are going to fail, I want them to at least fail trying something original.

After they made their first lesson I encouraged the student-teachers to "adapt" tasks to the JHS. By "adapt" I meant reduce the content and think about how they could change the task to encourage the JHS students' language use. For some reason, they seemed to perceive my "adapt" to be completely destroy. We have one week until the lesson and I will meet with the graduate students tomorrow. Let's see what happens.