2. It is systematic:
3. It provides frequent feedback:
Intensive Intervention Toolkit–Examples for teachers to intensify math and reading instruction.
Hattie, J., &., Gersten, R., & Chard, D. J. (2000). The underlying message in LD intervention research: Findings from research syntheses.
Timperley, H., Vaughn, E., Exceptional Children, 67, 99–114.(2007). The power of feedback. Review of Educational Research, 77, 81–112.