Maureen (2008) cited to Ward (1961), and stated that the concept differentiated instructions was first developed when it is known that children have different educational, emotional, social levels of development and needs, which can be affected by students’ learning. This is why he recommended that teachers need to plan instruction to meet those needs.
One of the leading experts of differentiated instructions is Tomlinson. Brad (2011) mentioned that Academic search Premier revealed that since 1995 Tomlinson has authored more than 50 publications based on differentiated instructions. Tomlinson (2014) mentioned that social constructivism (ZPD) and multiple-intelligence gave her the way to work on differentiated instruction.
Tomlinson (2001) also, have specified more or the same sort of concept on differentiated instruction. She believed that the very beginning of differentiated instruction has started since from the one-room schoolhouse. At that time, students with different ages were there in these schoolhouses, and for all these students, the same component to be taught by a local teacher. For a single teacher, teaching for different aged students would be very challenging. In her research study, Tomlinson (2001) also has mentioned that teachers had a challenge for providing instructions to many students of different ages, different disabilities, and learning levels at the same time.
According to Levy (2008) teachers and professors emerged to promote principles of differentiated instruction when teaching became increasingly challenged for a diverse group of students. When Vygotsky (1975) was working on his theory of learning (ZPD), he found that learning affects differentiated instruction. He described ZPD as:
“ the distance between the actual developmental level as determined by individual problem solving and level of potential development as determined through individual problem solving under adult guidance or in collaboration with more capable peers”.
According to Woolfolk (2013), the ZPD plays an important role in differentiated instruction, because it allows teachers to recognize an entry point for each student’s learning needs. Therefore, this helps to develop that student’s learning potential.
I believe that Vygotsky’s theory of social constructivism could be the foundation of differentiated instruction. On the other hand, it was Gardener’s (1993) multiple intelligence theory that promoted ideal for how student learning differences might be observed. Gardener argued that there are many ways to be intelligent according to this multiple intelligence theory. These include linguistic, logical-mathematical, spatial, bodily kinaesthetic, musical, interpersonal, and naturalistic intelligence. This intelligence helped to categorize learner variance. Furthermore, Gardener stated, that these multiple intelligences allow teachers to see through clearly the potential in every single student. This allowed teachers to stop labeling students as intelligent or unintelligent. Furthermore, Willingham (2004) stated that multiple intelligence theory is generally used as a tool by educators for understanding learner variation and an important part of differentiated instruction
As mentioned before, Tomlinson is one of the leading experts on differentiated instruction. Tomlinson (2004) argued that all the students are different from each other, therefore, they should be taught in such a way where learning differences could be addressed. For these learning differences, she mentioned that the content, process, and product of a lesson can be differentiated. Furthermore, she added, differentiating the content, process and product work-out with each other to support one another and is cycled through as every single student grows and develops in their own learning capacity.