Edgar,
I have read the documents and I have some information.
Here it is:
Not all students are alike. Differentiated instruction presents an avenue for multiple options for receiving and processing information.
It requires flexibility on the teacher's part to change curriculum and teaching methods rather than expecting the students to change themselves.
Differentiated Instruction is based on the premise that instructional approaches should vary and be adapted in relation to individual and diverse students in classrooms.

What is Differentiated Instruction?
This is a process to approach teraching and learning for studennts of differing abilities in the same class. The intent of differentiating instruction is to maximize each student's growth and individual success by meeting each student where he or she is, and assissting in the learning process.
Tomlinson (2001) identifies three elements of Differentiated Instruction
namely content, process and product
content
Several elements and materials are used to support instructional conten
Process
Flexible grouping
Proper classroom management
Product
Intinial and on-going assessment
Students are active and responsible explorers
vary expectations and requirements for students
Guides that make differentiation possible for teachers to attain:

• Clarify key concepts and generalizations
• Use assessment as a teaching tool to extend versus merely measure instruction
• Emphasize critical and creative thinking
• Engaging all learners is essential
• Provide a balance between teacher-assigned and student-selected tasks.

http://www.cast.org/publications/ncac/ncac.diffinstruc.html