The following are the standards for skills preschool students should have by the end of their pre-kindergarten education that specifically apply to literacy. A complete description of all areas of curriculum can be found here.
I would really recommend going to the site and looking at listening and speaking standards and social-emotional standards - these can give you ideas of what sort of skills you can expect of your students and also what behaviors you need to support. Honestly, for preschoolers, most of the valuable learning that takes place is in social-emotional development; preschoolers’ brains and bodies are made for playing with their friends.
Teaching skills more advanced that those outlined here are not BAD, per se (challenging students is a good thing), but if students appear frustrated and resistant behaviours increase it may be an indication that students are not ready to learn those particular skills.
Content Standard 1.0: Students know and use word analysis skills and strategies to comprehend new words encountered in text.
-Recognize environmental print and symbols (print and other symbols, other than books, found in the physical environment, such as street signs, billboards, cereal boxes, beverages, commercial logos, etc.).
-Identify some letters in own name.
-Identify the initial sound of own name.
-Demonstrate an awareness that print carries a message.
Content Standard 2.0: Students use reading process skills and strategies to build comprehension.
-Use pictures to aid comprehension.
-Ask questions or make comments pertinent to the story being read.
-Identify the front of the book and know how to turn the pages when reading.
Content Standard 3.0: Students read to comprehend, interpret, and evaluate literature from a variety of authors, cultures, and times.
-Retell a story with the aid of pictures, props, or a book.
-Predict what will happen next in a story and respond.
-Listen and respond to rhythm or rhyme.
-Listen and respond to age-appropriate material for a variety of purposes.
-Listen and respond to poetry and prose.
Content Standard 4.0: Students read to comprehend, interpret, and evaluate informational texts for specific purposes.
-Demonstrate an understanding that printed material provides information.
-Recall information from an event, text, or picture.
-Respond to or ask a question about an event, text, or picture.
-Follow, with teacher assistance, a simple pictoral direction.
Content Standard 5.0: Students write a variety of texts that inform, persuade, describe, evaluate, or tell a story and are appropriate to purpose and audience. (All children this age are not developmentally ready to produce representational work.)
-Experiment with writing tools and materials in response to information.
-Experiment with writing tools and materials to communicate.
-Experiment with writing tools and materials in response to a familiar experience.
-Experiment with writing tools and materials in response to literature.
Content Standard 6.0: Students write with a clear focus and logical development, evaluating, revising, and editing for organization, style, tone, and word choice.
-Share ideas for class writing.
-Organize ideas, through group discussion, with teacher assistance.
-Dictate words, phrases, or sentences to an adult recording on paper.
-Share drawings with others.
Content Standard 7.0: Students write using standard English grammar, usage, punctuation, capitalization, and spelling.
-Attempt, with a model, to write the first letter of first name.
-Attempt to spell own first name.
-Use letter-like approximation to write name and/or other words or ideas.
-Demonstrate beginning techniques for using various writing materials.
-Trace and progress to copying basic shapes (eg horizontal line, vertical line, X, plus sign, circle, etc).