What are the basics of getting a classroom (or a whole school) started using PRESS?  We have all had preliminary 1 day training.  Would it be a class-wide (school wide) screening test?

We use any passages, books that are at an appropriate reading level for our students.  Remember, if you are working on fluency (phrasing, expression, prosody, using punctuation) you want to be sure your students can read accurately 95% of the passage.  So, Read Naturally, DIBELS, A-Z, text companies provide several passages for fluency (but use a grade or two below), and current reading books if at the correct accuracy level are wonderful as well.  I used There's a Boy in the Girl's Bathroom for one of my 5th grade students working on fluency - we read together and then he was interested enough to continue on his own as well.  So, when we met to work on fluency, he just read from where he had left off.  He is well above benchmark as a 6th grader now (it was a great success story).  Best of luck!!

This is a great resource and the passages are free!

https://dibels.uoregon.edu/resources

We use many of the same resources named by other PRESS users.  Another site I found was West Virginia Reading First Explicit Phonics Lessons that is AMAZING for extending the Phonics intervention and providing quick practice with the phonics skills taught.

Florida Assessments for Instruction in Reading (Ongoing Progress Monitoring Oral Reading Fluency Grades 1-5)