I wanted to give B a chance to experiment with same and different and I wanted to make sure he understood the concept. I put two stickers on each card. Some of them matched and some of them didn't. I used lids as sorting trays.
B looked at the stickers and decided if they were the same or different. He loved this activity, but I had so many cards that he only wanted to do it once. There were a few tricky ones that had the same character on them but different colored backgrounds.
If he decided that the two stickers were different I'd ask things like, "How do you know?" "Why?", "Which part is different?".
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