Check out how I made a magic decoder for a B hunt! I started by drawing a big “B” on poster board, then filled it with red hearts. Inside each heart, I used a blue colored pencil to write half Bs and half other letters, so some hearts contain “B” while others do not. Next, I scribbled over those letters with red pencil, hiding them in plain sight. The secret is placing a red magnet tile (or red film) on top—this “decodes” the red scribbles, revealing which hearts actually have the letter B. It’s

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