I have this vocabulary power flip book which was bought a couple of years back. I put it in our study room, just regularly flip to new words whenever we were in the study room.
Once in a while, I will point out the word and asked our eldest kiddo to pronounce it and then I will explain to the rest of our kiddos what the word meant. My plan is to leave it there, subtly mentioned to kiddos whenever we are in the study room. Once, I forgot all about the flip book and our eldest kiddo suddenly asked me what the word on the flip book meant. Oh wow, paying attention huh?
So I continued as per normal, teaching when the opportunity presents itself, no pressure, not too subtle hahaha...
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