Advertisements capture consumers’ attention and motivate them to buy certain products. Similarly, teachers need to sell science to students by walking the talk of research-informed best practices. Magic signs with (dis)appearing messages (or color-changing letters) provide both a visual participatory analogy for and concrete example of the kind of interactive curriculum-instruction-assessment practices called for by standards documents. In this activity, an invisible, colorless message becomes colored and legible when it is sprayed with colorless household ammonia.