This is my third time through the Common Core Algebra 1 curriculum with Standards Based Grading and the online book based on ck-12 modules. Our school is moving towards proficiency based grading, so I've made some changes to line up with that.
My course has used 30-ish standards for the entire year and I've been using a version of quizzing based on Dan Meyers' blog post from forever ago. I think students benefit from more summative assessments than this rotating quiz schedule allows, so I've grouped my 38 standards ("learning targets", in other systems) into 10 units (also called "proficiencies" in other systems) so they can have unit tests along with the standards based quizzes. I still rotate all the standards through the quizzes, they see them twice in class and can retake twice with me, but there is now a summative unit test about once a month that can't be retaken. Right now I'm averaging all these scores to make a traditional number grade, but when our school moves over to proficiency based report cards, the grade will most likely be reported based on mastery of each proficiency.
I have also created a library of videos (screencasts of me teaching each standard) and practice problems that are posted on the class website. The students can access these for extra practice for the assessments. I have also reorganized the book and all of the classwork so it is very obvious which standard they connect to. This should make it easier for a student to see how they are doing on each standard prior to the unit test.
If a student wants to retake a standard, they have to show the homework and classwork from that standard, plus show some extra work they did from the online resources. I have a Google form they fill out to check off that they've done that, plus the form emails me to give me some warning that I need to have a quiz ready. Our school has just moved over to one 30 min advisory period in the middle of every day that we manage with Enriching Students software. This will make it easier for students to schedule time to retake quizzes.
I also have an extensive collection of classroom activities that I've collected from years of following people's blogs and Twitter feeds. This makes it fairly straightforward to have a variety of interesting things to do in an 80 minute block. I would like to use more of the clever problem solving activities that I have found online, but the Algebra 1 Common Core curriculum still has a lot of individual skills in it, so I don't have as much time for that as I'd like.
I am happy with how this is going so far, I think everything is organized in a way that makes it straightforward for the students to know what is expected of them. I think that education is moving towards students taking more control of their learning, information is so readily available that it seems reasonable to give them the ability to pick what they want and learn the way that they want. There are many ways to meet proficiencies and I believe schools will be offering students more independence in the ways that they get there. I have structured this course so that a student can get what they need in several different ways and they get experience in looking online for the materials that they need to be successful.