I used these with Let's Try 1 Ch 8 to great enthusiasm. Each activity took a whole class period after warm up, but you could also speed the activity up. Let me know if there's any questions!
Split the class into groups
Explain that each picture is something magnified under a microscope, and the color might be slightly different than what they're expecting.
Show the slides and give the kids time to think about what each item is. (2 minutes was plenty for us)
Give out simple hints during this time like, "It's red," "It's small," "It's in the classroom," "It's on a human," whatever you think your students would understand.
I wrote out a list of the answers in Japanese to give to my HRT so she could help give hints too (or just show them the PPT ahead of time). We used some Japanese during hint time.
Groups say their answer one by one. Prompt them with "What's this?" It's okay to say things in Japanese, but if they know the English, enocurage them to use it! Reveal the correct answer and give points to groups who got it right.
This one uses more of the items that are in the textbook (food and animals). It still might be a good idea to review words before you start.
Students secretly choose one item, and come up to the front of the class and give out hints. Color, shape, size, that sort of thing. Japanese hints are okay too.
Their classmates raise their hands and try to guess! Have students use, "That's right!" or "sorry, no."
Keep going as long as you have volunteers or time! Be sure to switch to the animals slide.
You could also print out the Powerpoint, and have students work in groups to give out quizzes to give students more chances to practice.