Instructional Practices

Decoding the Acronyms: Understanding MTSS, PBIS, and RTI in Education

7 Min Read
Mtss pbis rti hero WF1757800

The Ever-Evolving Classroom

It seems that no matter the state, district, or classroom, the U.S. education system is always evolving and being fine-tuned to the needs of the children it serves. In theory, this evolving structure is always serving the children’s best interests. In practice, ever-evolving often translates to a complicated string of re-education and re-adjustments for teachers. Just when teachers are finally comfortable implementing one approach in the classroom, they are asked to implement a new approach.

Common acronyms that show up are “MTSS,” “RTI,” and “PBIS.” The generally accepted practice of MTSS—or Multi-Tiered System of Supports—is often shown alongside RTI, or Response to Intervention, and PBIS, or Positive Behavioral Interventions and Supports, which are two approaches that fall under MTSS’ umbrella. MTSS, RTI, and PBIS are all frameworks designed to prevent students from falling behind from academic and behavioral standpoints.

What Is MTSS?

The Center on Multi-Tiered System of Supports (the MTSS Center) defines MTSS as “a proactive and preventative framework that integrates data and instruction to maximize student achievement and support students’ social, emotional, and behavior needs from a strengths-based perspective.” The framework divides students into three main tiers.

  • Tier 1 represents the general instruction that students within their core classroom.
  • Tier 2 represents targeted supplemental intervention delivered using differentiated instruction.
  • Tier 3 represents individualized, intensive intervention after a student has been identified as requiring additional support or instruction, behaviorally and/or academically.

This multi-tiered system is traditionally visualized as a pyramid, with the wide base representing students receiving Tier 1 core instruction, the middle part representing students receiving Tier 2 support, and the narrow top representing some students—ideally though not always a small portion of the student population—needing Tier 3 intervention.

RTI tiers image

MTSS is an approach designed to tackle the needs of the whole child holistically. It encompasses academic, social, emotional, and behavioral aspects of the student experience. It includes systems that account for universal support, along with both targeted and intensive interventions. This article walks through two of those systems: Response to Intervention, or RTI, for an academic system, and Positive Behavioral Interventions and Supports, or PBIS, for a behavioral system.

Mtss whole child triangle WF1757800

The MTSS Center recommends a tri-annual screening process to properly identify students who are at risk for poor outcomes. Once a student has been identified as needing additional support, teachers use an evidence-based intervention, which might include supplementary materials such as Waggle or intensive intervention materials such as Read 180 and Math 180.

What Is MTSS vs. RTI?

MTSS is the overall framework in which students who need additional support are identified and met with a series of approaches to improve their learning outcomes. RTI, or Response to Intervention, focuses on academic screening and intervention and can work in conjunction with MTSS using the same tier structure. There are four core characteristics of RTI:

  • High-quality, research-based instruction in general education
  • Continuous progress monitoring
  • Screening for academic and behavior problems
  • Multiple tiers of progressively more intense instruction

These core characteristics ensure that students are routinely screened and monitored for poor academic outcomes. Research shows that prevention is an essential facet to RTI in order “to maximize student achievement and to reduce behavioral problems.” And while both models take a data-driven and multi-level approach, when comparing MTSS vs. RTI, RTI is traditionally focused on improving academic outcomes for struggling students.

What Is MTSS vs. PBIS?

MTSS as an overall tiered framework can also be used in conjunction with PBIS, or Positive Behavioral Interventions and Supports. The aim of the PBIS framework is to identify early warning signs of poor behavioral outcomes in students and provide immediate intervention with a series of approaches. The objective of PBIS is not to punish but rather to utilize positive reinforcement and reinforced education about behavioral expectations. These behavioral expectations are upheld through careful screening of the mental health and well-being of students.

AASA, the School Superintendents Association, describes PBIS as “a framework rooted in a positive discipline philosophy that celebrates students for appropriate behaviors…. PBIS uses a proactive approach to teach and model appropriate behaviors, and reinforce positive expectations for behavior through affirmations and rewards.”

What Is RTI vs. PBIS?

While the purpose of RTI is centered around academic outcomes, PBIS is centered around behavioral outcomes, including behavior that stems from social and emotional challenges. RTI and PBIS complement one another in determining the root cause of student outcomes, as behavioral and academic struggles often are identified together.

To illustrate how RTI and PBIS work together, let’s walk through a hypothetical case study. Alex, a fifth grader, has been screened tri-annually and has performed at above average levels in his academics. To date, Alex has received little to no disciplinary measures in school. Recently, however, his teacher has observed him disrupting other students in class and has had to intervene on several occasions. Additionally, he was seen bullying another student on school premises on a few occasions. His last three math scores were significantly lower than his usual score results, as he generally excels in the subject. However, he continues to excel in social studies and English. His teacher notifies school administration and arranges a collaborative plan with the school psychologist and Alex’s parents to determine the root cause of the behavioral problems and for Alex to receive more intensive and individual instruction in math. In this scenario, Alex would temporarily be placed in a Tier 2 or 3 category for math and receive a personalized approach to alleviating the stressors that are causing poor outcomes while encouraging and fostering his progress in the subjects in which he still excels.

MTSS, RTI, PBIS, and the Individuals with Disabilities Education Act (IDEA) of 2004

Although MTSS, RTI, and PBIS have become prevailing approaches among schools in the U.S., they are not federally mandated. At the risk of introducing one more acronym, the 2004 amendments of the Individuals with Disabilities Education Act, or IDEA, does, however, mandate that states permit “a process that determines if the child responds to scientific, research-based intervention.” In other words, states can either require or permit school districts to implement RTI but cannot prohibit it. As of this writing, Colorado, Connecticut, Florida, Idaho, Louisiana, Rhode Island, West Virginia, and Wisconsin require their schools to use RTI completely and exclusively.

Neither MTSS nor PBIS are mentioned in the IDEA itself but are referenced in later advisory statements issued by the Department of Education and successive acts, such as the Every Student Succeeds Act of 2015 (ESSA). Statements issued by the U.S. Department of Education recognize MTSS, RTI, and PBIS as legitimate approaches that states can and often should adopt.

Challenges with Illustrating MTSS

While the tiered MTSS pyramid is the most common way of illustrating the different tiers of support, it may be helpful instead to visualize a functional model where student performance falls along a scale associated with placement from assessment. This is a more accurate way to reflect where students are in relation to being on-grade level and can help administrators determine the right supports and interventions for their unique situations.

Shaped 2023 RTI bell curve with title WF1735931

It is important to understand that MTSS, RTI, and PBIS are not one-size-fits-all approaches. They are designed to be tailored to the needs of individual districts, schools, classrooms, and students. In fact, individualized approaches require that academic challenges are spotted by educators with a familiarity with the student and addressed in a targeted way before the challenges are magnified. It is for this reason that teacher buy-in is of the utmost importance for consistent and effective application.

No matter what framework a school has in place, teachers are the implementers and the most important component of MTSS, RTI, and PBIS. It is up to the administration to gain teacher buy-in, as uneven application could potentially lead to students in need falling through the cracks. However you visualize the interventions that students need and whatever frameworks your school has in place, they are all in service of improving student outcomes.


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The views expressed in this article are those of the author and do not necessarily represent those of HMH.

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