Looking for a writing assignment. I would
 

like to connect with Solar System if possible. I do a Writer's Workshop format but am having a hard time to connecting the writing cross-curricular. I have already done a personal narrative and persuasive essay writing. Any guidance would be great. Thanks!

letter writing
 

Maybe have them write a letter from a planet they pretend to visit. They would have to use a specific number of facts about the planet and use the proper format for a friendly letter. The oldest I've taught is 3rd, so I'm not sure what the standards are in 5th but if they are still practicing addressing envelopes at this point, you could include that.