Sequential: skills are taught in a logical order, systematically and sequentially moving from the most foundational skills to the more complex ones. Teachers who use this type of teaching also continue to practice and review previously learned skills.

Cumulative: Instruction is based on concepts previously learned. Students continue to practice and automatize previously learned skills before moving to new learning.

Sequential

Structured literacy classrooms follow scope and sequences that outline the sequential, systematic order for word recognition and language comprehension instruction. 

The National Reading Panel’s (2000) research on such systematic instruction is clear:

• Systematic phonics instruction produces significant benefits for students in kindergarten through 6th grade and for children having difficulty learning to read.
• Across all grade levels, systematic phonics instruction improved the ability of good readers to spell.

Phonics is not the only space for sequential, systematic instruction. Jennings and Haynes (2018) document implications for sequential syntax instruction as well: 

• A sentence hierarchy systematically introduces sentence structures from simple to complex sentences.
• Utilizing a sequential approach improves:
  • Use of varied sentence types
  • Sentence length and complexity
  • Grammatical accuracy

Because sequential instruction intentionally builds, it differs from an opportunistic approach to instruction that teaches new skills as opportunities arise.

Cumulative instruction begins with a strong foundation and provides the essential building blocks to continue learning. Cumulative instruction is a critical component to instructional design (Gagne et al., 1992). Educators should plan instruction that:

• Recalls prior learning and knowledge before sharing new information. Use strategies such as asking questions about prior experiences, probing for understanding of previous concepts, and connecting past course information to the current topic.
• Uses a clear instructional routine to present worked examples, ensuring each step is thoroughly explained.
• Integrates previous skills and concepts and reinforces new learning. 

Critical to cumulative instruction is the need for a detailed scope and sequence which outlines the material to be taught, a systematic order of instruction, and the associated learning outcomes (See “Sequential”).

Video to include phonics – simple to complex; scope and sequence examples

IDA Perspectives 2019 (Charles W. Haynes, Susan Lambrecht Smith, and Leslie Laud)

Cumulative:

Video: In this elementary example, the teacher automatizes letter names and sounds already taught before moving into the new skill.