Multi-Tier System of Supports (MTSS)/ Response to Intervention (RtI)

Table of Contents

  • School-wide screening
  • Progress monitoring
  • Tier 1
  • Tier 2
  • Tier 3
  • Fidelity of implementation
  • IDEA and RTI
  • Resources
  • Voices from the field
In this chapter the focus will be on response to intervention (or instruction) RTI, which now falls under the umbrella of the more encompassing Multi-tiered System of Supports MTSS.In addition to the RTI academic focus, MTSS includes a focus on the behavioral needs of students under the title of Positive Behavioral Supports and Interventions (PBIS)

WikiDaily, (2020). Response to Intervention, Content is available under CC BY-SA 3.0

In education, response to intervention[1] (commonly abbreviated RTI or RtI) is an approach to academic intervention used in the United States to provide early, systematic, and appropriately intensive assistance to children who are at risk for or already underperforming as compared to appropriate grade- or age-level standards. RTI seeks to promote academic success through universal screening, early intervention, frequent progress monitoring, and increasingly intensive research-based instruction or interventions for children who continue to have difficulty. RTI is a multilevel approach for aiding students that is adjusted and modified as needed if they are failing.

In terms of identifying students with specific learning disabilities (SLD),[2] RTI was proposed as an alternative to the ability–achievement discrepancy model, which requires children to exhibit a significant discrepancy between their ability (often measured by IQ testing) and academic achievement (as measured by their grades and standardized testing). Methods to identify students with SLD have been controversial for decades[3] and proponents of RTI claim that the process brings more clarity to the Specific Learning Disability (SLD) category of the Individuals with Disabilities Education Improvement Act (IDEA 2004),[4] while opponents claim that RTI simply identifies low achieving students rather than students with learning disabilities.

RTI is originally a special education term that has broadened into a general education framework that involves research-based instruction and interventions, regular monitoring of student progress, and the subsequent use of these data over time to make a variety of educational decisions, including, but not limited to SLD eligibility.[5][6][7] To facilitate this broadened conception of RTI, there was a shift to labeling this as one of the approaches of a Multi-Tier System of Supports (MTSS) occurring in schools and the professional literature.[8] The key to the RTI process is the application of scientifically based interventions that have been demonstrated to work in randomized controlled trials.[9] A goal of the RTI process is to apply accountability to the educational program by focusing on programs that work rather than programs that simply look, sound, or feel good.

RTI follows a number of core assumptions:[5]

  1. The educational system can effectively teach all children.
  2. Early intervention is critical to preventing problems from getting out of control.
  3. The implementation of a multi-tiered service delivery model is necessary.
  4. A problem solving model should be used to make decisions between tiers.
  5. Research based interventions should be implemented to the extent possible.
  6. Progress monitoring must be implemented to inform instruction.
  7. Data should drive decision making.

School-wide screening

The first level of data collected in the Multi tired system of support/ RTI process, comes from universal school-wide screenings. These screening assessments are typically given to all students within targeted grade levels, and cover basic academic subjects such as reading and mathematics. Most screening measures aim to be practical and efficient to administer, with the goal of identifying students who may require further assessments and interventions.

To evaluate student performance on the screening measures, scores are compared to specific criteria (criterion referenced) or to broad norms (norm referenced). When specific criteria are used, cut scores are established to evaluate students against a specific level of proficiency (e.g., achieving a score of 15 or above); in a normative comparison, students’ scores are compared against those of a larger group (e.g., scoring above the 25th percentile compared to a national sample of 3rd grade students).

Screenings usually occur three times per year (fall, winter, and spring), and the data from these assessments help to guide instruction through the three tiers of the RTI process. This is important not only for identifying students who are having difficulties, but also for identifying possible areas of improvement in the general classroom instruction in the cases where too many students fall below expectations.[15] Because a single universal screening at the beginning of the year can over-identify students who require preventive intervention, the National Research Center on Learning Disabilities recommends that schools also integrate at least five weeks of weekly progress monitoring to identify students who require preventive intervention.[16]


Core curriculum in the classroom should be research-based and field tested. This means, based on evidence from congregating research, that the core curriculum contains all the fundamentals found necessary to efficiently teach reading and has a recognized record of achievement. Such curriculum is to be delivered by “highly qualified” teachers adequately trained to deliver the selected instruction as intended, that is, with fidelity to design.

Progress monitoring and a multi tiered service delivery

Progress monitoring is a set of assessment procedures for determining the extent to which students are benefiting from classroom instruction and for monitoring effectiveness of curriculum.

Curriculum-based measurement (CBM)[17] is often used to collect data on interventions and their effectiveness to determine what works best for an individual student. Additional methods are attempted until students “respond” to the intervention and improve their skills. Students that do not respond, or respond at significantly low rates, may be deemed to have learning disabilities, rather than simply learning difficulties.

Progress monitoring is the scientifically based practice of assessing students’ academic performance on a regular basis for three purposes:

  1. To determine whether children are profiting appropriately from the instructional program, including the curriculum.
  2. To build more effective programs for the children who do not benefit.
  3. To estimate rates of student improvement

Three tiers of Scientifically Research-Based Interventions (SRBIs) of increasing intensity incorporate the key components of Multi tiered system of support/ RTI and help ensure the academic growth and achievement of students.

Tier 1

The first tier states that all students receive core classroom instruction that is differentiated and utilizes strategies and materials that are scientifically research-based. Assessment in the classroom should be ongoing and effective in that it clearly identifies the strengths and weaknesses for each learner. Any necessary interventions at this level are within the framework of the general education classroom and can be in the form of differentiated instruction, small group review, or one-on-one remediation of a concept.

Progress monitoring in Tier 1 uses universal screening assessments to show individual student growth over time and to determine whether students are progressing as expected. In this process, data are collected, students are identified using benchmark scores, and measurable goals are set for the next data collection point for those who display difficulties. The team then follows a problem-solving process to determine interventions for at-risk students that will work within whole-class instructions. The classroom teacher implements the interventions, observations are conducted to ensure the fidelity of the classroom instruction, and the problem-solving team periodically reviews the progress of students.

[The Swift Center]. (2017, Jul. 27). MTSS: Universal Support [Video File]. Retrieved from  (3:31 minutes)

Tier 2

In the second tier, supplemental interventions may occur within or outside of the general education classroom, and progress monitoring occurs at more frequent intervals. Core instruction is still delivered by the classroom teacher, but small groups of similar instructional levels may work together under a teacher’s instruction and/or guidance. This type of targeted instruction is typically for 30 minutes per day, two to four days per week, for a minimum of nine weeks. This targeted instruction may occur in the general education setting or outside in a smaller group setting with a specialized teacher (such as a Literacy Support teacher for struggling readers).

In Tier 2, the main purpose of progress monitoring is to determine whether interventions are successful in helping students learn at an appropriate rate. Decision rules are created to determine when a student might no longer require extra interventions, when the interventions need to be changed, or when a student might be identified for special education.

[The Swift Center]. (2017, Jul. 27). MTSS:Additional Support [Video File]. Retrieved from  (2.40 minutes)

Tier 3

Tier three is for students who require more intense, explicit and individualized instruction and have not shown sufficient response to Tier 1 and Tier 2 interventions. This type of targeted instruction is delivered for a minimum of two 30-minute sessions every week for nine to twelve weeks. The interventions in this tier may be similar to those in Tier 2 except that they are intensified in focus, frequency, and duration. The instruction in Tier 3 is typically delivered outside of the general education classroom. Programs, strategies, and procedures are designed and employed to supplement, enhance, and support Tier 1 and Tier 2 instruction by remediation of the relevant area and development of compensatory strategies. If Tier 3 is not successful, a child is considered for the first time as potentially having a learning disability.

In some cases, Tier 3 is considered to be special education, with instruction being provided to individual students or small groups by special education teachers in place of general education instruction (rather than as a supplement). Initial goals are established through an individualized education program (IEP), which is guided by the results of a comprehensive evaluation, and ongoing progress monitoring helps to direct the teaching process. Special education instruction likely will be considerably longer than the 10 to 12 weeks of supplemental instruction delivered in Tier 2 and beyond. The frequency of special education instruction depends upon student need, and the criteria to exit special education are specified and monitored so that placement can be flexible.

[The Swift Center], (2017, July 27). MTSS:Intensified Support. [Video File]. Retrieved from  (2:29 min.)

Multi tiered system of support/RTI implementation

The number of schools implementing RTI continues to grow and 61% of schools surveyed in 2010 indicated that they had fully implemented or were in the process of implementing RTI.[21]  RTI is primarily implemented by grade-level teams or professional learning communities as part of a school-wide problem-solving plan. Previous research found that implementing RTI resulted in several positive outcomes such as reductions in students referred to and placed into special education, more students passing state accountability tests, and increased academic skills among students at-risk for reading failure.[22]

Fidelity of implementation

In an Multi tiered system of support/ RTI model, fidelity is important at both the school level (e.g., implementation of the process) and the teacher level (e.g., implementation of instruction). Although the concept of fidelity of implementation is supported by research and is generally viewed as common sense, there are practical challenges associated with achieving high levels of fidelity. Factors that can reduce fidelity when implementing instruction include:[23]

  • Complexity of the interventions and the time required to implement them.
  • Inaccessibility of required materials and resources.
  • Low perceptions/expectations of effectiveness (teachers may not fully commit to an intervention if they believe that it will not be effective, or if it is inconsistent with their teaching style)
  • Low numbers, expertise, and motivation of those who deliver the interventions.

Factors that can increase fidelity when implementing a Multi tiered system of support/ RTI model include:[24]

  • Well-functioning professional learning communities
  • Using a universal screener that is brief, aligned with the curriculum, result in reliable data, and is validated for screening decisions.
  • Using a data-management system that is easily accessible by classroom teachers
  • Implementing interventions that address the skill deficit of students.
  • Identifying and addressing class-wide needs.
  • Establishing well-defined decision rules.
  • Clear leadership from the building principal.
  • Ongoing training and professional development.
  • Key stakeholders working together in a flexible manner to improve student learning.
  • Use of standard-protocol interventions for tier 2.
  • Not making entitlement (i.e., special education disability identification) decisions until the RTI system is in place and well established.

Relationship between IDEA and RTI

The 1997 Individuals with Disabilities Education Act (IDEA) was revised as the Individual Disabilities Education Improvement Act (IDEIA) and signed into law in 2004, and it became effective in July 2006.[34][35] According to the law, a specific learning disability is a disorder of one or more of the basic psychological processes that adversely affects academic achievement in one or more domains (e.g., reading, writing, math, language). There are three methods of SLD identification under IDEA, as defined in §300.8(c)(10) (OSERS Final Regulations-8/06):

  1. A discrepancy between “ability” and “achievement”
  2. Failure to respond to scientific, research-based intervention
  3. Alternative research-based procedures for determining whether a child has a specific learning disability

(The “third method” is often considered a “processing strengths and weaknesses” model.)

The 2004 reauthorization of IDEA makes mention of RTI as a method of part of the process of identifying SLD:

  1. In diagnosing learning disabilities, schools are no longer required to use the discrepancy model. The act states that, “a local educational agency shall not be required to take into consideration whether a child has a severe discrepancy between achievement and intellectual ability[…]”
  2. Response to intervention is specifically mentioned in the regulations in conjunction with the identification of a specific learning disability. IDEA 2004 states, “a local educational agency may use a process that determines if the child responds to scientific, research-based intervention as a part of the evaluation procedures.”
  3. Early Intervening Services (EIS) are prominently mentioned in IDEA for the first time. These services are directed at interventions for students prior to referral in an attempt to avoid inappropriate classification, which proponents claim an RTI model does. IDEA now authorizes the use of up to 15% of IDEA allocated funds for EIS.[36]

RTI was included in the regulations due to considerable concerns raised by both the House and Senate Committees regarding proponents of RTI claims about the use of IQ tests to identify learning disabled students. There was also recognition in these committees of a growing body of scientific research supporting methods of pre-referral interventions that resolved learning difficulties short of classification. However, the final regulations also allow a third method of SLD identification, often considered a processing strengths and weaknesses model.

The IDEA Committee Conference Report (CCR)[37] discusses the use of scientifically based early intervention programs, describes a model response-to-intervention program, and recommends the development of the most effective implementation of responsiveness to intervention models. The report describes such a model as an essential service for reducing the need to label children as disabled.

Through the establishment of the RTI process in IDEIA, schools could shift from a model that required teachers to wait for students to fail, to a model of prevention, offering extra support to students during the learning process.[38]

Concerns and criticisms of RTI for SLD classification

Criticisms of the RTI model first surfaced in 2004 when IDEA identified it as a viable method for use in SLD eligibility determination[44] Some feel that RTI is valuable for prevention, but see little empirical support for using RTI to determine learning disabilities, and have concerns that it could be used to delay or deny services to children with learning disabilities.[45]

Why is it important to ensure students with disabilities are part of multi-tier frameworks?

In this video, Maryl Randle, a doctoral candidate in Special Education at Michigan State University & NCII Coach for the Swartz Creek School District, addresses the importance of ensuring that students with disabilities have access to supports across the tiers of a tiered framework, especially intensive intervention.
[National Center on Intensive Interventions] (2014, Oct. 2014).Why is it important to ensure students with disabilities are part of multi-tiered frameworks? [Video File]. Retrieved from   (2:07 min) 

voices from the field

Voices From the Field

Teacher candidates reflection on how is MTSS/RtI implemented in their schools and on progress monitoring.


In our school, every classroom actually has a time period in the day (30 minutes long) that is called RTI. It is also sometimes just called Intervention. During this time, students’ needs are met with whatever they may need depending on what tier they are in. The Tier one students use this time to do either ST Math (a computer-based supplemental math program that uses games to reinforce the lessons being taught at math time) or on other days they do Typing Agent (a computer-based program that teaches typing skills. Sometimes they also read books of their choice. The students who are in Tier 2, (as identified by reading benchmarks/level, math assessment results, and other assessments), receive targeted support during this RTI time. Some students receive a push in, which is when a title 1 teacher like me goes into the classroom and sits with a student or small group of students (4 or less) to do a guided reading lesson, phonics lesson, or Leveled Literacy Intervention lesson. Some push ins are also just to give the student extra support during the whole class lesson. Other students may be pulled out of the classroom for these same types of lessons. Students who are in Tier 3 go to their special ed teacher’s room or to another work area to work directly with their special ed teacher on their own specific IEP goals and modified curriculum during this time. Caitlin Dubisz


My school recently adopted the Response to Intervention Model. Under this model, they adhere to school-wide reading and math screenings and follow the three tiers of instruction outlined in RTI (Lombardi, n.d.). Tier 1 students are served solely through classroom instruction, and teachers are expected to differentiate their instruction according to students’ needs and interests.  Teachers are also responsible to monitor students and see which ones might need reading or math remediation.  Unfortunately, math remediation is not easily accessible and is only being provided for students who are in the TIER 3 group and consequently have been referred for or are already on an IEP. Students who are in Tier 2 do have access however to reading specialists and a speech therapist.  As aforementioned, Tier 3 students are normally on an IEP and have access to math and reading specialists who provide support and accommodations as spelled out in the student’s IEP. Mallory Wilson


Every student takes a STAR test in the Fall, Winter and Spring each year. The test includes both math and reading. The reading benchmark and observations are also something that is used when determining additional support. There are specific reading intervention teachers who work with Tier 2 and 3 students. Students are pulled during a WIN (What I Need) block for a reading group that focuses on the students’ needs. No new content is taught in the class during this time that way the students are getting support without missing something in the classroom.

     Reading benchmarks are a tool that is used. These are completed at certain times throughout the school year for all students to make sure they are making appropriate progress. If the students are not making progress, then they are brought to the reading interventionists and evaluated to become a part of a Tier 2 or 3 reading group. Tools specific to my SP are fluency reading probes, word reading lists, reading passages with comprehension questions, math probes with specific problems that are based off the student IEP goals. The tools vary depending on student needs.

     Another thing to know about that, although students may have Tier 2 or 3 support, if they are still struggling and not making progress in the classroom, a classroom teacher can bring the student to the school PAT team. This team helps with additional support for the student. Sometimes this can lead to a special education referral. Other times this can lead to support or ideas from the team to help find solutions for the student. All of these help the student in a multitude of ways! Anonymous


The school that I work at does have an RTI program in place. Students that are referred to Intervention will have their classroom teacher collect specific data to better assess the needs of the student.  That data gets analyzed by a team that meets regularly as a target team. RTI is a way to move along a student to get focused attention on the specific skills that need attention. I have seen the first and second grade classes regularly do DIBELS reading testing. Since last spring*, our school has increased the use of diagnostics and assessments of me-ready for grades 1-5, especially over remote learning. (schools closed due to COVID) Tracey O’Brien


I work in an elementary school with K-4th grade students.  We use an RTI model.  All kindergarten students are screened prior to the beginning of the year and divided into classrooms to create diverse groups of students.  The classroom teachers monitor progress and if they see an area of concern they submit the student’s name to our TSST (Teacher Student Support Team) team.  A meeting is scheduled to discuss the students’ areas of need with the appropriate staff. This may include any or all of the following:  LEA representative, school psychologist, school counselor, classroom teacher, reading specialist, math specialist, special education teacher, speech pathologist, occupational therapist, behavioral specialist, paraeducator, vision and hearing specialists or any other specialist needed.  The team presents the data and decides how to best help the student. This process elevates the student to level two or RTI.  During the meeting strategies, accommodations, behavior plans, and interventions are agreed upon and implemented for a set period of time.  This time varies depending on the student, however, the team agrees upon a follow up meeting scheduled to decide if the interventions are successful  or if more assistance is needed.

Tier 3 occurs when the TSST agrees that the level 2 interventions are not sufficient and additional targeted interventions are needed for the success of the student. They may then be recommended for further testing to determine if there is a qualification for special education placement. Sheri Gauvin


The school I work at does have a formal MTSS/RTI system implemented to provide support to students that require tier 2 and 3 interventions.  In the area of language arts/reading students are “benchmarked” at the beginning of every school year.  If the student is reading at the expected grade level they do not require intervention outside the classroom and receive their instruction in the classroom via the tier one format.  Students that are not reading at the expected grade level are designated as needing tier two or tier three interventions based on their benchmark results.  These tier two and three students still receive the core curriculum in the classroom with their general education teacher.  For reading support my school has a reading intervention room with three reading specialists that support the students in tier two and three.  Students go to the reading room for 30 minutes one to five times a weeks based on the amount of intervention needed. Tim Fahey


Tier 2 academic interventions include math groups that meet twice a week with the math coaching team. After six weeks, these groups are assessed based on attendance and performance data in order to see if the students should be discharged from the group (the goal was completed, such as mastering multiplication tables), continue or change direction. Usually, around 15% of the student population of a school accesses these services. Anonymous


Each classroom is an inclusive setting, giving all students access to the general education curriculum. The students that receive tier 2 interventions have their work differentiated and modified, either by the classroom teacher or by a special education teacher/educational assistant. This allows all students to be able to complete the classroom curriculum. Tier 2 students also are included in small groups within the classroom, working with the teachers on math and literacy skills. The students are grouped together by skill level, which allows them to all practice the same material. Students with IEPs complete discrete trials, given by their paraeducators, which tracks their progress one their individual IEP goals. Chelsea Hoadley

Monitoring Student Progress

Student data essentially drives the bus for instruction for a teacher.  Using consistent, frequent progress monitoring allows a teacher to address skill deficits in students, refine and improve teaching strategies, particularly within areas/concept a child or children may struggle with, and identify those students who may need additional support outside of a group setting.  Of particular note, teachers should avail themselves of CBMs, curriculum based measurement, as offered through the school’s established curriculum tools.  One example is  Fresh Reads Fluency checks that are part of the Reading Street program.  Weekly fluency checks help show growth or lack of growth over a sustained period of time.  Other progress monitoring tools can include both formative and summative assessments.  Formative assessments are ongoing during the instruction of the skill and can include such items as exit tickets, pop quizzes and informal teacher questioning.  Summative assessments such as mid-year tests, end of unit tests and year end tests do not necessarily help make course adjustments, but help with giving the teacher over time feedback on skill areas he/she should improve their instruction on. Jacqueline Godin


Some of the tools used for progress monitoring at the school I work at are the Northwest Evaluation Association – Measures of Academic Progress (NWEA-MAP), the Eureka Math Program, and the Fountas and Pinnell Reading Program.  The NWEA-MAP tests reflect the instructional level of each student and measures growth over time.  They are state-aligned, computerized adaptive tests that are administered in the fall, winter, and spring to provide teachers with valuable information regarding where the students are at in math and reading, and how far they have advanced. Eureka is our math curriculum and provides teachers with daily informal assessments, as well as unit assessments.  Fountas and Pinnell is our reading curriculum, and includes benchmark assessments that give teachers information regarding what level each student is at, and when they require extra help to achieve grade level reading. Judith Moore


 I see the Learning Lab model as being very accessible because it is open to any student at various flexible times. This model, I believe, makes it easier for a student with an IEP who chooses to keep their IEP private, because any student can participate at any time. Walking in the door of the learning lab does not mean that a student has an IEP. Everyone needs some help now and then, and this method, I believe, circumvents any stigma a teenager may perceive about being noticed by his peers as a student with an IEP. I am offering this feedback because someone I know quite well used to refuse to accept supports that would possibly show his peers that he needed special education services. However, he often utilized the learning lab and he felt very comfortable doing that. We may prefer that high school students would feel very open and socially secure about special education support and having an IEP, but I see an added benefit of the learning lab model as an option for students because it removes that from the equation so the student who feels the need for that privacy will get help when needed.  Michaela Donati

References can be found at the bottom of the article at: 

Image source

Reading- Image by Peggy und Marco Lachmann-Anke from Pixabay

MTSS graphic Paula Lombardi