Final answer:
The minimal recommended size for classroom presentation posters is larger than 8 1/2 x 11 inches, with 24 x 36 inches being a common starting point for good visibility and detail.
Step-by-step explanation:
The minimal size recommended for posters for most classroom presentations is larger than standard printer paper size, which is 8 1/2 x 11 inches. Classroom posters should be large enough to ensure that visuals are clear and legible at a distance to all viewers in the room.
A common starting size for classroom posters is 24 x 36 inches, as it allows for a good balance between visibility and detail. It is crucial to make sure that all text is readable from a distance, which generally means using large, legible fonts and arranging content with a clear structure, possibly using the left-to-right flow both horizontally and vertically to guide the viewers' eyes.
The imagery should be bold and the central message of the poster should be immediately apparent to ensure effective communication.