Here is an introduction to the braille alphabet. It offers information on memorizing the code, a visual of the braille cell, and a page with blank cells that students can fill in to "write" in braille. You could also have students use puffy paint, gems, or any tactile stickers to make it 3D! This can also be used as a resource to teach family members, teachers, and peers of students who are blind.
*Reminder: this is only a brief introduction to the braille alphabet and does not include information about contracted braille.