There are two varieties of lessons that I generally try to steer clear of. The first is those having to do with free time or weekends, on account of the Japanese typically do nothing with their free time. Exhibit A:
"So, Megumi, what are you into?"
"eh?"
"What do you do in your free time?"
"heh?"
"What is your hobby?"
"Ah! Hobby! Yes!... Sleeping!"
"... That's not a hobby"
"I like sleeping. It is my hobby"

Everything youve heard about workaholic Japanese is basically true. After spending a whole lifetime in cram schools and doing overtime at work, they just dont really know what to do with themselves when theyre off work.
Ive asked, a few times for advice from other teachers on how to deal with this problem.
"So, I really dont wanna do C10, but its the only one open. Any advice? They never have anything interesting to talk about"
"Yeah. I always make them imagine they have a life, and do roleplays from there, give it a try"
"You mean I should say imagine you have a life?"
"Nah, they wont get that, its too casual. Assign them a life, yknow, like this weekend, I went to Tokyo Disney, then went out for some fusion cuisine at a new restaurant in Ginza'"
I dont like doing that kind of thing, it seems patronizing. So I usually just grit my teeth and prepare myself for a very long forty minutes.
The other kind of lesson I dislike revolves around offering opinions. The Japanese are notoriously averse to openly showing their standpoints on things unless they already know what theyre expected to say. This is a result of cultural practice that places great value on the segregation of personal feelings (known as honne, rhymes with "phone-neigh") and what you "should say" to keep the harmony "tatemae"). Tatemae is the bread and butter of the Japanese business world. The individual is expected to sacrifice for the group, and this most frequently involves keeping your opinions to yourself. That means not whining about work, or a headache, or the fact that, as a Japanese, you only have sex 43 times a year, on average. When an opinion is elicited, they will typically do one of two things: First, they will defer, passing the question on to someone else.
"So, Haruka, whos the best baseball player in the world?
"Mmmm... I dont know... Who do you think is the best baseball player in the world?"
Second, they will agree with you:
"I really think Adolph Hitler was perhaps the worlds greatest advocate for peace in the 1940s"
"Yes, I think so too"

There are three pass/fail aims for lesson D48, or "Expressing opinions". The first is to ask for and provice opinions regarding sports figures, movie stars, and other celebrities. The second aim of the lesson is to support those opinions with a reason. The third is to agree or disagree with those opinions. Some students will repeat that lesson three times, and still never pass the third aim. They can always agree, but disagreement is beyond the scope of their tatemae restricted social graces. Such was my experience. Until saturday.

"Ok, very good work everyone. I heard lots of good supporting reasons, and a good variety of agreement phrases. But I didnt hear anyone disagree with anyone else. I asked you all to argue about who was the best player on the Japanese national soccer team, and I dont believe that it was so easy for you to just change your minds just like that."
Sheepish grins and silence ensue.
"So listen... Im going to ask you to do that last excercise over again. This time, if I dont hear all of you disagree vehemently, Im going to fail every last one of you. Do you understand?"