Those were some awesome ideas. I teach first and second and use centers. Here are some that I use:
1. Journals: Use story starters and have students finish the story and illustrate.
2. Silent reading: Just having practice silent reading. Maybe have them write a summary of a chapter/book read.
3. Squiggle: Students make an illustration of a squiggle on a piece of paper and write a story to go with it.
4. Top Ten: Make a list of Top Ten whatever (animals, countries, things to do in the summer, etc. Could be anything) When the students have a list they can do lots of different things with the list like: putting them into sentences, adding endings, writing them in different types of letters, making stories, putting them in ABC order, adding to the list, categorizing them
5. Letters and Notes: Have students write letters to various people.
6. Listening comprehension: Students listen to a story on tape and answer questions about it, tell and illustrate their favorite part, retell the beginning, middle, and end; create a different ending, discussing favorite characters
7. Reading the Room: Students have a clipboard and walk around the room recording different words/phrases: rhyming words, words that end in -s or -es, -ing words, base words, etc. or whatever skill you want them to work on
8. Find it in a Book: finding vocab. or other types of words in a book or even types of sentences (For younger students, telling sentences and questions but for older ones they can find commands, contractions, adjectives, etc.)
9. Flip Books: fold a piece of construction paper in half (hamburger style) fold in half again two times (hot dog) and cut halfway up to make 3-4 slits that flip. You can have students write something on the front (types of sentences) and illustrate and give an example inside the flip. I use them for: types of sentences, B M E, vocabulary words, parts of a sentence, describing characters, parts of a story, etc.
10. Character Award: Students give a favorite character an award and reasons that the character should receive it.
11. Book Talk: Describing your favorite part of the story, only telling the gist; selling the story so that others would want to read it
12. Leveled reader activities: usually a packet of things that will coincide with the leveled reader during that week
13. Bingo: I have a couple of Bingo card games that the students can play. They love to be the person who reads the card. I think they have them for older students too.
14. Making Words: Students have letters to cut out (or use letter tiles or precut letters). Students make as many words as they can with the given letters and try and find the "secret" word that uses all of the letters.
I have a couple of books that have different ideas for literacy. Two that I can think of off the top of my head are: Alternatives to Worksheets and More Alternatives to Worksheets. They have a lot of really good ideas that even bigger kids can do.
Hope this helps.