Daily 5, Reading workshop, and spelling

I go back to work Tuesday and the kids come on Thursday. I have now hit the time of year where my brain will not turn off and I can't sleep. It's terrible. I woke up at like 3 and had the worst time going to back to sleep. Although when I was asleep, apparently I pushed Chris and told him to get off me. I don't remember that at all. I do remember thinking I had no space to sleep.Oh well. In my tossing and turning, I started thinking about school and what was going on. I got a great brainstorm about spelling. I've been blogging about how I want to make a change in spelling and make it more on my students' levels. But I've got a lot of changes going on this next year with full implementation on Daily 5 and math workstations. In all the common core and assessment talk that we went through last week, one thing stuck out in my brain. Using pre-assessments, to push kids further. I've always done a "pre-test" in spelling on Wednesday but that's not truly a pre test. This year I plan to give a pretest on Monday on the week's spelling words. If the student knows 90% of the words then  that student will be given a little bit harder list of words for the week. I am not firm in my 90%. I am not sure how to handle that. If they get a 90% on the test then that means they missed one. I don't know that they need to focus on 9 words that they already know if they only missed one. (Any input on handling this would be appreciated). The second thing I'm not sure of is where to get the new list of words. I'm thinking that the words would still follow the rule that the rest of the class is focusing on. For example, the first week of spelling words are short a words. They are basic cvc words. I think several of my kids will know all these words. What I'm thinking is that I would find a list of words that still uses short a but involves some blends and digraphs. Any suggestions of where to get these words would be appreciated. I've also been thinking about the tasks that I'm asking kids to do during the spelling time. In the past we've done rainbow spelling. While I think they need some practice writing the words, I'm not sure that it's the best use of time. I added word sorts last year and I think that was great. We also practiced putting the words into alphabetical order. What other activities should I include that is worth the time?
Another thought going through my mind at 4 in the morning was how I was going to structure Daily 5. I'm starting to panic about actually implementing the structures of Daily 5. I have been setting up my room to support a daily 5 structure. I have set up the classroom library so more of my books are accessible for the kids. The next step was a writing area and a word work area. I'm worried that I don't have enough materials for word work. I think I might be panicking and am going to be more likely to fall back into my literacy stations comfort zone. So maybe I need a pep talk from my bloggy friends knowing that I can do this. As I've been reading more about reading workshop, I know that I want to incorporate this into my teaching as well. So I'm trying to figure out how to merge the two ideas. The way I'm thinking of this is that I use my read to self and reading workshop time as the same time. Instead of giving my kids the choice of read to self as part of the daily 5, that would be separate. I want there to be a focused time on reading and increasing their skills. Any thoughts on this from my bloggy friends? So this is what I was thinking about at 4 in the morning.
On a side note, I'm participating in the Back to school sale at TPT starting tomorrow. I also have all my items on my TN store on sale as well. So be sure to check it out.