Once you have designed the learning sequence, it is time to do a thought experiment on how well it will work for the whole range of your students.  To do this, first imagine being a high-achieving student who masters new material quickly.  Now march through the sequence, observing it through her eyes.  Does every part of the process support genuine learning?  Are there moments where she is likely to be bored?  If she finishes an activity more quickly than her peers, is there always something meaningful for her to do?  Does she have ample opportunity for enrichment activities and/or sharing the wealth with less successful students?

Now imagine being one of your least successful students going through the same sequence.  Perhaps she has less motivation to learn, has a poorer background in your subject, or simply takes longer to understand the new material.  Is the process you designed responsive to her needs at every point?  Will she enter the panic zone at any juncture in the process?  Are complex skills broken into sufficiently small subskills for her to be successful?  Is remediation available to her whenever she needs it?

What the learners need should be the central criterion in creating the design.  If those needs are met for the whole range of students in your class, your design is ready to implement.  If not, add or modify elements to make the process more responsive to every student at every point in the sequence.