Tier 1 Reading Interventions: What They Are and How to Make Them Work

Imagine a typical Tuesday morning in a second-grade classroom. The teacher, dedicated and hardworking, looks at a growing stack of intervention referral forms. Despite best efforts to provide small-group support during the literacy block, the list of students who seem to be falling behind continues to expand. This is a scenario played out in schools across the country: Teachers are working themselves to exhaustion to provide remediation, only to find that the number of students requiring help is outpacing the available resources.

When a significant portion of a class struggles to meet literacy goals, it is rarely a reflection of the teacher's dedication or the students' potential. Instead, it is often a signal that the foundational layer of instruction needs strengthening. This article will define Tier 1 reading interventions, explain who they serve, describe what effective Tier 1 instruction looks like in practice, and demonstrate how tools like Lexia® Core5® Reading help educators deliver high-quality instruction at scale.

What are Tier 1 reading interventions?

To understand what Tier 1 intervention is, we must first look at the Multi-Tiered System of Supports (MTSS) or Response to Intervention (RTI) framework. Tier 1 is the universal, whole-class level of reading instruction. It is the core reading program that every student receives every single day.

A common point of confusion among educators is the term "intervention" itself. In many contexts, "intervention" implies pulling a student out of the classroom for specialized help. However, Tier 1 reading interventions do not encompass remediation or pull-out services. Rather, they refer to the strengthening and differentiation of the core classroom reading program so that it meets the needs of all learners right where they are.

Think of the MTSS pyramid as a guide for resource allocation, wherein:

• Tier 1 serves approximately 80% of students through the core curriculum.

• Tier 2 serves roughly 15% of students who need supplemental, targeted support.

• Tier 3 serves about 5% of students who require intensive, individualized intervention.

The 80% benchmark is critical: If fewer than 80% of your students are meeting grade-level reading benchmarks, the challenge likely lies within the quality of Tier 1 instruction rather than in individual student deficits. Once you strengthen the Tier 1 core, fewer students will require the more intensive resources of Tiers 2 and 3.

Who does Tier 1 serve?

A common misconception is that Tier 1 is only for on-level students—in reality, Tier 1 interventions are for all students. In a healthy MTSS model, students who move into Tier 2 or Tier 3 for supplemental support continue to receive Tier 1 instruction. The intervention layers on top of the core instruction; it does not replace it. When Tier 1 is robust, roughly 80% of students should be able to reach grade-level benchmarks through this whole-class instruction alone.

Furthermore, strong Tier 1 reading instruction is an essential component of educational equity. It is especially critical for multilingual learners, students from under-resourced communities, and other historically underserved groups who may not have access to supplemental literacy resources outside of the school building. High-quality Tier 1 instruction ensures that every child, regardless of their background, has access to the evidence-based instruction they need to become proficient readers.

What does effective Tier 1 reading instruction look like?

Effective Tier 1 instruction is not accidental—it is explicit, systematic, and grounded in the science of reading. It requires a careful balance between whole-class instruction (where new concepts are introduced to everyone) and small-group instruction (where teachers can provide targeted practice based on student needs).

To move the needle for all students, educators must move toward a proactive approach that anticipates and addresses learning gaps within the core block.

6 key components of strong Tier 1 reading instruction

To build a foundation that supports 80% or more of your students, your Tier 1 program should include these six essential pillars:

1. Explicit instruction in foundational skills

Strong Tier 1 instruction must include systematic and explicit teaching of phonological awareness and phonics. Students need to understand the relationship between sounds and letters in a logical, step-by-step sequence rather than through incidental exposure.

2. Vocabulary and background knowledge development

Reading comprehension is deeply tied to what a student knows. Effective Tier 1 reading instruction intentionally builds a student's mental warehouse of words and world knowledge through rich text discussions and thematic units.

3. Oral reading fluency practice

Fluency is the bridge between decoding and comprehension. Tier 1 should provide regular opportunities for students to practice reading texts aloud with accuracy, appropriate speed, and proper expression.

4. Text-based comprehension strategies

Comprehension is not a set of isolated skills, so effective instruction must focus on deep engagement with complex text. This includes teaching students how to monitor their own understanding while using strategies like questioning and summarizing to extract meaning.

5. Formative assessment and progress monitoring

A strong Tier 1 program is data-driven. Teachers must have a clear pulse on student progress to know who has mastered a concept and who needs additional Tier 1 intervention within the classroom setting.

6. Small-group differentiation

While the core content is delivered to the whole class, the application of that content should happen in small, flexible groups. This allows the teacher to provide extra scaffolding for some while offering enrichment for others.

Common pitfalls that weaken Tier 1

Even when delivered with the best intentions, certain practices can inadvertently undermine the effectiveness of your core instruction. Recognizing the following pitfalls is the first step toward fixing them.

• Lack of differentiation involves treating the whole class as a monolith wherein every student does the exact same task at the exact same pace.

• Weak foundational skills instruction relies on balanced literacy approaches that prioritize guessing or context clues over systematic phonics.

• Misaligned curriculum uses materials that do not align with the science of reading or state standards.

• Lack of actionable data leaves educators flying blind without frequent data to inform who is struggling and why.

• Over-referral to higher tiers is characterized by referring students to Tier 2 or 3 before ensuring that Tier 1 instruction is high-quality and implemented with fidelity.

The role of assessment in Tier 1 reading interventions

Data is the engine that drives effective Tier 1 instruction. Conducting universal screening—typically three times a year—helps identify which students are at risk. However, screening is just the beginning.

To truly differentiate in real time, you need ongoing formative data that allows you to adjust your small groups and teaching strategies weekly or even daily. For many busy educators, the challenge is finding the time to test students. This is where Lexia’s Assessment Without Testing® can become a game changer. Using digital tools that gather data while students work, teachers can gain a clear picture of student needs without sacrificing valuable instructional time to administer tests.

How Core5 supports Tier 1 instruction

Strengthening Tier 1 instruction at scale is a significant challenge, which is why many districts turn to Core5. Built on the science of reading, Core5 is a program designed specifically to support Tier 1. It provides a single, adaptive platform that serves students of all abilities, whether they are working on level, require acceleration, or are currently at risk.

Core5 uses an adaptive blended learning model that fits seamlessly into the whole-class block. While the teacher works with a small group, other students engage with personalized digital paths that target their specific skill gaps.

Personalized learning paths for every student

The heart of Core5 is its three-step instructional branching, which ensures that within the same whole-class block, every student gets the exact level of support they need on a personalized path.

1. Scaffold

If a student struggles with a specific task, the program immediately adjusts to provide a scaffolded, simplified version of the skill. This temporary support helps students build confidence by breaking down complex concepts into more manageable steps. The program prevents students from becoming overwhelmed and keeps them engaged with the learning material by addressing misconceptions in real time.

2. Guided practice

Once the student demonstrates improvement through scaffolded support, they move into guided practice. During this phase, the program provides targeted feedback and hints that coach the student through the concept rather than simply providing the correct answer. This instructional layer allows students to practice their skills with just the right amount of assistance to ensure successful, independent application.

3. Advance

After a student achieves mastery, they are seamlessly advanced to the next level of the curriculum. This ensures instruction remains consistently challenging and accelerated learners are never bored or held back while waiting for a whole-group lesson to conclude. This continuous forward momentum allows every student in the classroom to reach their full potential at their own unique pace.

Research-proven results

When you choose a tool for Tier 1, it must be evidence-based. As one of the most researched literacy programs available today, Core5:

• Features 20 peer-reviewed, published studies validating its effectiveness

• Carries an ESSA "Strong" rating, the highest level of evidence defined by federal law

• Is proven to significantly increase the percentage of students working at or above grade level by the end of the school year

How do you know if your Tier 1 program is working?

As you evaluate your current literacy framework, use the 80% benchmark as your primary diagnostic. Are at least 80% of your students meeting grade-level reading targets on your universal screening? If not, it's time to look closer at your Tier 1 practices.

Signs of a strong Tier 1 program

• Most students (≥80%) are reaching benchmarks without extra help.

• Instruction is explicit, systematic, and follows a logical scope and sequence.

• Small-group time is used for targeted, data-driven practice.

Signs of a weak Tier 1 program

• Large numbers of students are being referred for Tier 2 or Tier 3 interventions.

• Teachers feel they are constantly re-teaching concepts that were already covered.

• There is a lack of clear, actionable data to guide daily instruction.

If you find your Tier 1 program needs strengthening, you are not alone. Many teachers and administrators find that shifting to a science of reading-based approach supported by adaptive technology is the key to turning the tide.

Build a stronger Tier 1—and stronger readers—today

Strong Tier 1 instruction is the most powerful implement for schoolwide literacy improvement. When we strengthen the core, we don't just help the students who are struggling; we elevate the entire classroom. Implementing explicit instruction by utilizing real-time data and leveraging tools like Core5 can help you ensure that every student in your classroom has a clear path to literacy success.

Ready to transform your Tier 1 instruction? Contact us today to learn more about how we can support your school's literacy goals.