In as very real sense, no one teaches Literacy. Not even Literacy teachers. Literacy is developed through practice and use. The more literacy skills are practiced, the more developed they will be. Thoughtful Learning has an interesting article that lists and defines the various kinds of literacy students need in order to succeed. The article states:
Students' use of media has far outstripped educational use, and students will continue to adopt new media long before teachers can create curricula about it. It is no longer enough to teach students how books, periodicals, and TV shows work. Students need to learn how to critically analyze and evaluate messages coming to them through any medium.
Therefore, regardless of subject area, students require skills to simply understand and use information they are processing in multiple ways and for multiple purposes. I encourage you as a teacher, regardless of what age you teach or which subject you teach, to think about the following questions:
How is the information being presented to the students? Which medium is used?
What supports do the students need to be able to understand the information?
In which form am I asking the students to repeat and/or use the information?
Which literacy skills are required throughout the lesson?
Are additional literacy skills required in order for the students to succeed?

These questions will help you intentionally plan for literacy development to take place. Requiring multiple literacy skills simultaneously is fine, as along as you are intentionally aware of that and are providing the necessary support for your students throughout.
TIP: Intentionally plan for literacy development in all of the classes you teach.
Coming up next, “Students today can’t read or write well.” Stay tuned...