Working idea: Elementary school students and special needs students respond well to relia (real world objects). This helps them connect new language to familiar items and concepts.
Preparation:
Step 1: Get a big bag. Raid your closet and/or a thrift store. Fill said big bag with different kinds of clothes. Daiso has cheap hats, socks, and ties if you want to include those items.
Step 2: Get a little container of 1 yen, 5 yen, or 10 yen coins. Fake coins work too, but I like using real money (or as I and my teacher cousin call it "money money"). Just tell the HRT and students you need the money back. Work with whatever you feel comfortable with.
In class:
1: Practice the attached script with the students at least twice. You can write it on the board or project it on a TV from your PC if that's available.
2: Demonstrate with the HRT or another teacher.
3: Then let the students go shopping!
I gave my students two coins so they got two chances to try. This worked pretty well from my experience. Depending on time, class size, and the number of clothes you have in your bag, you could give them 1 coin or 3 coins.
When I tried this with my elementary school special needs class, they had a lot of fun.
BONUS TIP!!
Pair with an easy colors based game as a warm-up. This activity is great for practicing pairing colors and objects. Let them get those linguistic gains!!