Acellus Learning Accelerator

Acellus researchers study how students learn to develop technologies rooted in cognitive science that accelerate the learning process. acellus has been deployed at 7,000 schools nationwide., watch video, what makes acellus a learning accelerator.

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Acellus Vectored Instruction

The key to accelerated learning.

Acellus Vectored Instruction ® is a powerful intervention strategy that fills critical holes in a student’s understanding to accelerate learning. When a foundational deficiency is diagnosed, Vectored Instruction goes as far back as necessary, even pulling from prior grade-levels if required, to fill in the missing foundational knowledge.  Once the student has restored that requisite foundation, they resume the course where they left off, better prepared for success.

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Prism Diagnostics

Identifying the holes that hold your student back.

Acellus Academy courses integrate Prism Diagnostics ® , an innovative technology that identifies holes in each student’s background knowledge. When a deficiency is detected, the system immediately responds with customized personalized instruction to reinforce a concept the student is struggling with. If the student continues to struggle, Vectored Instruction is triggered.

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Professionally-Filmed Lessons

Engaging video instruction brings each subject to life.

Acellus courses utilize professionally filmed video lessons to spark the interest of students. Acellus Academy works with some of the most qualified teachers in the country to create lessons that are both engaging and effective. These captivating videos, combined with interactive course materials, provide an online school experience that inspires a love for learning.

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Acellus Writing Tutor

Helping students become exceptional writers.

Teaching effective writing is one of the toughest challenges in distance learning. The Acellus Writing Tutor ® is designed to tutor students as they write, giving immediate feedback on grammar, spelling, vocabulary, and even writing style. With this personalized feedback, students quickly discover that they can become exceptional writers.

Acellus STEM-10

Acellus STEM-10 is a ten-year coding program with a full pathway of courses to prepare students for high-demand careers in STEM-related fields.

Beginning in the third grade, students are immersed in hands-on learning using interactive robots that teach the fundamentals of coding.

Building on this foundation year-by year, students advance their knowledge and coding skills to become job-ready when graduating from high school.

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Over 400 Courses - Grades K-12

Acellus Academy’s course catalog includes courses in all core subject areas, grades K-12, as well as electives, Advanced Placement (AP), Career & Technical Education (CTE), and STEM focused pathways.




Social Studies


Language Arts




Computer Science


Foreign Language

Course excerpts.

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Science – Excerpts

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Mathematics – Excerpts

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Language Arts – Excerpts

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Social Studies – Excerpts

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Career & Technical Education – Excerpts

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Music  – Excerpts

View Enrollment Options

Enrollment in Acellus Academy is open year-round. Select the option below to review tuition and enrollment options.


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Gold edition, the revolutionary system designed to transform the academic advancement of students in special education., empowering students…, powered by cutting-edge ai-driven tools, this groundbreaking platform adapts to the unique requirements of each learner. gold edition empowers students who may have faced challenges in their studies, enabling them to bridge the gap and reach grade-level expectations successfully..

Acellus Empowers Students

Grant Funding Available for Special Education

The Acellus Special Education Matching Grant is a program to help schools implement the Acellus Gold Edition to meet the needs of students in special education programs.

By leveraging this grant, schools can effectively address the learning gaps experienced by students with severe challenges, fostering their academic progress and facilitating a smooth transition back into mainstream education.

This program equips teachers with a wide range of built-in supports, professional development, and training. Through this ongoing training process, teachers not only gain confidence in utilizing the system but also sustain a culture of continuous achievement and motivation.

What Makes Acellus a Learning Accelerator?

Building on modern research, Acellus developers study the way students learn, identify obstacles to learning, and experiment with different techniques rooted in cognitive science to discover the ones that accelerate learning.

Vectored Instruction

Acellus recognizes that addressing gaps in foundational knowledge is crucial to student success .  To overcome this obstacle, Acellus devised a groundbreaking solution known as Vectored Instruction, which serves as an effective remedy for students struggling with missing essential concepts.

Acellus Writing Tutor

The Acellus Writing Tutor uses Intelligent Interaction to tutor students as they write, giving immediate feedback on grammar, spelling, vocabulary and even on the writing style. This is a long awaited game changer on our ability to teach writing in the distance learning environment.

Professionally-Filmed Video Lessons

Acellus courses employ expertly produced video lessons to ignite students’ curiosity. Collaborating with some of the nation’s most skilled educators, Acellus crafts lessons which are not only impactful but also captivating. These videos , coupled with interactive course materials, deliver an online educational journey that fosters a genuine passion for acquiring knowledge.

Cognitive Learning Drills

Acellus is putting cognitive science to work. Acellus presents lessons in a way that fills up the student’s working memory so that the new bits of knowledge go directly into implicit memory.  

Memorizing important information is critical for advancing to more difficult concepts. Examples include math facts and physics equations. Beginning readers need to memorize common words because the time needed to sound out words phonetically often degrades comprehension.  

The Acellus Effect

Transforming Education’s Landscape

The Acellus team has embarked on a mission to revolutionize students’ learning experiences through an innovative online learning system. 

The manifestation of the Acellus Effect is shown when students who were struggling start experiencing success , when they grow in their self-esteem, when their attitudes change, and when there is a pervasive positive shift in the attitudes of both teachers and parents towards the education of their students.

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Helping our students perform on grade level…

“ Acellus has truly been a game-changer for helping our students perform on grade level,” said Adolfo Melara, Superintendent at George I Sanchez Charter School. “Students come to our school with varying levels of readiness. Acellus has been an equalizer that bridges achievement gaps to address inequities in academic achievement. “

Adolfo Melara, Superintendent

George I Sanchez Charter Schools − Houston, Texas

Acellus Effect- Students Experience Success

Acellus is equipped with powerful tools that alleviate the burden of routine tasks from the teacher’s daily schedules. Simultaneously, it offers actionable guidance on supporting individual students, streamlining the teacher’s role and ensuring that attention is focused where it is most urgently needed.

From our perspective at Acellus, teachers constitute the bedrock of learning within our educational institutions. Recognizing the pivotal role they play, Acellus advocates for providing the recognition and support essential for their triumph.

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White Paper:

Unveiling the acellus effect.

by Dr. Roger Billings


Students 3-4 years behind are performing on grade level…

“Our high school serves students in an alternative setting where it is not uncommon for students to be as much as 3-4 years behind grade level. Acellus has given us the tools to meet  these students at their level and get them performing on grade level,” explains Kevin Morris, Principal at Mount Olive Innovation and Technology High School. “ Acellus has helped to restore student confidence and put students, who were once helplessly behind, on a path to success.”

Kevin Morris, Principal – Mount Olive Innovation and Technology High School

Duarte Unified School District − Duarte, California

Acellus Courses

Acellus offers an expansive selection of standards-based courses K-12. Acellus courses are professionally filmed with some of the best equipment available in the cinematic industry.

The combination of incredible footage, outstanding teachers, and content that makes learning relevant to the real-world, makes Acellus videos captivating and interesting – igniting the student’s interest in learning.

Elementary Sample Videos

Middle school sample videos, high school sample videos, deployment options.

One System – All Your Students

Special Education

Multi-sensory instruction that is custom designed for students with special needs. classroom-tested to be effective in getting students back on grade level., credit recovery, effective, standalone system for credit recovery. discovers deficiencies, triggering vectored instruction., multi-year stem program for elementary through high school. self-contained teacher built in..

The Acellus STEM Lab program empowers math and science teachers to offer effective coding and robotics courses without the need for extensive additional training. The STEM Lab includes video-based coding courseware, and a programmable robot. By combining self-contained instruction with interactive tutoring to the student by the robot, Acellus is able to provide schools with STEM courses that can be up and running overnight.

Gifted and Talented

Rigorous courses developed to challenge and motivate even the most gifted students.

Learners who show evidence of high achievement, such as gifted and talented students, often have unique requirements that require specialized instruction in order for them to fully develop their capabilities. Acellus allows students to move forward on an accelerated path, and differentiates the instruction so that students with various skill levels are not held back. A special accelerated mode of Acellus has been developed specifically for gifted and honors students.

Career & Technical Education (CTE)

Cte courses taught by teachers with years of work experience. students are able to earn industry recognized credentials while in high school., english as a second language (esl), courses specially developed to help students from any ethnic background master the english language.

The Acellus Discover English courses are developed for students in ESL/ELL programs. They are ideal for students from any ethnic background and language that are learning English. This course utilizes the Universal Interaction Technique, developed by Roger Billings, so that the same course can simultaneously support students of various native tongues.


Powerful deficiency diagnostics combined with targeted intervention restores student confidence and achievement., social emotional learning (sel), social emotional courses including crisis intervention lessons for students and parents..

The Acellus SEL (Social Emotional Learning) courses focus on the importance of cultivating healthy relationships, a caring attitude, and the importance of one’s overall well-being and physical health. SEL inspires positivity, which will empower students to face the day-to-day challenges they will encounter in the real world. Separate courses have been developed for the elementary, middle, and high school levels. 

Before & After School Programs

Expansive selection of standalone courses ideal for stem, intervention, credit recovery and enrichment., summer school, video based, self-contained courses ideal for a diverse population of learners in summer school programs.

With a wide array of course offerings, and many diverse deployment options, Acellus is a perfect fit for Summer School programs. Schools can choose from over 300 video based courses, and are able to control the level of rigor for each course. This makes it ideal whether the goal is to help struggling students catch up, or provide an accelerated option for gifted students.

Advanced Placement (AP)

18 college board approved ap courses, teacher taught and effective as standalone option, ged & adult education, speciality courses designed for the ged, tasc and hiset. extensive array of career and workforce training courses., virtual learning, effectively teaching students over a distance., correctional education, teacher taught courses provided to students in a standalone, locked down environment., a program of the international academy of science.

The International Academy of Science is a nonprofit 501(c)(3) organization that has been advancing science and education for over 30 years. The Academy offers applied science undergraduate and graduate degree programs that prepare students with important hands-on skills and experience needed for success in the workplace.

Acellus was created by the International Academy of Science in 2001, and has since been adopted by thousands of schools across the country, and has provided education to millions of students in all 50 states and worldwide.

Acellus is an interactive learning accelerator. It combines technology and learning science to help students master content, learning more effectively (greater mastery) and efficiently (in less time). Backed by scientific research, Acellus delivers online instruction, compliant with the latest standards, through high-definition video lessons made more engaging with multimedia and animation. Each lesson is carefully designed to connect with previously learned knowledge like interlocking building blocks. Students can log in to take lessons from school or home, on any device.

Find out what it would cost to get Acellus for your school.

Acellus State Coordinators are available to provide you with more information on getting Acellus for your school.

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Online Homeschool Program

For the fully accredited online school option, please visit AcellusAcademy.com

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Included with Power Homeschool Subscription

Science LIVE with Acellus Creator Roger Billings

This weekly mentoring program encourages students of all ages to study hard and inspires a love for science. Using real-world examples, Roger Billings teaches students how to become “Inventioneers” who can turn breakthrough discoveries into useful inventions. Research shows that students who participate in this program improve academically and develop positive attitudes toward their schoolwork.   Learn More

What’s New at Power Homeschool!

New courses.

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High School English II

This course is designed to deepen students’ understanding and appreciation of literature while also developing communication skills. Read More

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Introduction to Geography

Students will explore topics such as maps, Earth’s layers, the forces shaping its surface, and the importance of managing its resources. Read More

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AP World History: Modern

In this course students explore major historical themes and develop crucial analysis skills necessary to analyze documented event. Read More

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Accounting II

This course emphasizes accountability, professional behavior, and ethics through real-world examples and case studies. Read More

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Enabling Tutoring Mode

You can enable Tutoring Mode on any of your student’s classes through the parent interface using the Acellus App.  Read More

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Enhanced Parent Account Interface

Several updates and enhancements have been added for Parents when managing their Power Homeschool Parent Account.   Read More

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New Tutorial: Retake for Credit

Students are able to retake steps to revisit previous lessons and improve their score. This feature is available through the student account. Read More

New to Homeschooling

Have questions, ask the homeschooling experts – parents.

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Introduction to Music Appreciation

New Course Announcement Introduction to Music AppreciationThis new Acellus® elementary elective - Introduction to Music Appreciation - takes students on an immersive journey through the fascinating world of music, spanning different historical periods and musical...

Flexible Online Homeschool Program Helps Family Live Their Dream

Flexible Online Homeschool Program Helps Family Live Their Dream

The Knapps found that this online homeschool program is flexible enough that they can do school on their own time and helps them get the best education.

Traveling Family Succeeding with Homeschooling

Traveling Family Succeeding with Homeschooling

  “We’re able to take it with us when we go, we can do it on our own time, it’s set at your own pace, and it takes all the busywork out.” - Tiffany Thompson   Louisiana may be their home base, but Aidan and his parents are constantly on the go - traveling...

More Homeschooling Resources and Information

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  •  Parent Guide to Getting Started with Homeschool
  • j How to Prevent Homeschool Burnout
  •  6 Tips for Transitioning from Homeschooling to College
  •  5 Ways Homeschooling Can Help Children with Disabilities
  •  Why Homeschooling is on the Rise

Homeschool Links:

  • Pros and Cons of Homeschooling
  • Homeschooling Basics (101)
  • Homeschooling Laws for all 50 States
  • How do Homeschoolers Get Diplomas?

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Science L!VE

With roger billings.

Learn about the Roger Billings Mentoring Program »

WATCH LIVE – Wednesdays, 7pm (CST)

News & Updates

EDUCATION TECHNOLOGY INSIGHTS:    “Acellus: Promoting Coding Literacy with Cutting-Edge Technology”  »

Science with Roger Billings

Tune in to Science L!VE with Roger Billings

Wednesdays at 7pm – cst, “ invest in yourselves…, you don’t need to have a big wallet to invest in yourself because you can get it with ‘sweat equity.’ you can earn it the way you invest in yourself and the potential of your future is the way that you apply yourself to learn.”, – roger billings.

Inspired by his own mentor, Bill Lear, the Roger Billings Mentoring Program was developed as a way to “give back,” supporting thousands of students with mentoring guidance through Science L!VE as well as helping cover student tuition costs.   Learn More About the Roger Billings Scholarship »

These mentoring forums are something that have personally helped me and is something I love so much and have come to appreciate. I love the amount of work and dedication that is put into it. Also knowing that it is something that Mr. B created for our own benefit makes me very happy. It’s a very kind and generous thing to do and I love it. Thank you.

Maria (Student)

I would really like to thank you for creating Acellus and for your talk. Your message is truly inspiring and motivates me as a parent to expect more from my children, to create for them the right environment to study and to grow and develop in order to change the world in the future. Finding Acellus and signing my daughter up for the program is the best thing that happened this year. I am sure it will open up the doors to new horizons for Sofia. You are doing such an important job by providing kids from different backgrounds with such amazing opportunities. We will continue watching your talks!

Oksana (Parent)

Thank you for doing your talk. Thank you for inspiring the world to do things that have never been done before. You have helped me to do so many things and me and my family want to say THANK YOU! I believe that Acellus can change the world for good, Acellus is amazing!

Daniel (Student)

I really love Acellus, when I started, it was really the first time I was really engaged and really excited about school and learning in a long time. I plan on continuing to use Acellus until I graduate, and hopefully accomplish great things in my future.

Alyson (Student)

We heard about Acellus through a friend whose daughter used the program. You are definitely reaching people. We have only been using Acellus for a week and it has been such a blessing for our family. My son loves being able to learn at his own pace. Thank you for this opportunity.

Joshua (Parent)

I am very impressed not just with the quality of the material presented here but the quality of human beings working here. I did not know who Acellus was at heart! I am happy and proud to be part of this organization…

Gloria D. (Parent)

Your Wednesday night class is so interesting. My grandparents can’t wait for Wednesday night. We watch it as a family. You are teaching them things they didn’t know.

Rylee (Student)

Thank you so much for all the work you do to provide us with the best education. Since the pandemic started my parents did not want to send us back to school and they didn’t know what they were going to do. One of my sister’s friend’s mom suggested this program to us and we love it. It is so much better than what we did in our previous school. It’s so easy to understand and the work is just the right amount. We are so thankful that we found this program. I’m in my last year of school and I’m going to be graduating in a couple of months.

Dane J. (Student)

Due to the pandemic my school had been forced to do online classes. Some family friends recommended Acellus to us and gave us very good references; so we decided to take the risk. This has been the best decision we have made; I have learned much faster, it makes me want to learn more, I have maintained good grades, my expectations about my future have changed, I am being able to achieve more. My parents are happy with Acellus and I’m really happy too.

Evelyn O. (Student)

I am looking forward to discussing this week’s Science L!ve with my son! This week has been a discouraging week for parents as they find out reopening plans for schools. As I sat on last night’s Board of Education meeting, I cannot tell you how happy I am that my son is receiving a quality education through Acellus. You saved us from distance learning last year. And I am grateful we are continuing my son’s education with you. At the dinner table tonight, he told me he doesn’t want to return to public school. You may have my son until high school as a student until he graduates from high school. Thank you!

Laura (Parent)

I have been with Acellus Academy for 2 years now, and I have been inspired by Dr. Billings and Dr. Angel to do better in my life and academics. Currently, I’m 18 years old and I have a hard time learning certain concepts. But Dr. Billings has helped me with that. He has inspired me so much that I feel like I can do anything that I am capable of. Some people have doubted me. It is much appreciated that you inspired me. I’m almost ready to graduate from this wonderful school! Thank you for making my learning experience more exciting! I really enjoy the videos.

Liberty S. (Student)

Dr. Billings: You always amaze me with your knowledge! I like the fact that you show how much you love sharing your knowledge, teaching us, and empowering us. Thank you for never being boring, and most especially always being genuine. Acellus Academy is genuine because it was born from a man who is genuine.

Bryan (Student)

I just want to say thank you for using a lot of your time to answer all of our questions, I imagine that you use up a lot of your time already so doing this shows how much you care about all of us.

Hugh T. (Student)

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What is Acellus?

Acellus is a learning accelerator.   Using video-based lessons combined with cutting-edge technology it has been found to accelerate learning, raise standardized test scores, reduce dropout rates and helps transition more students into careers and college.

Watch Video ›

Vectored instruction.

Vectored Instruction™ has changed the dynamic of online education. This technology is enabling students to master foundational skills they are missing that are prerequisites to success in their current course of study.   Vectored Instruction fills in the gaps while keeping students within their credit-level course, enabling them to complete their coursework with passing grades and get on track for graduation.

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Prism Diagnostics

Prism Diagnostics® identifies specific holes in students’ understanding of core concepts and responds instantly with customized videos focusing on that particular deficiency. The result is that every student receives personalized instruction – right at the moment when they need it most.

Watch the Video ›

Writing tutor.

The Acellus Writing Tutor uses Intelligent Interaction to tutor students as they write, giving immediate feedback on grammar, spelling, vocabulary and even on the writing style. This is a long awaited game changer on our ability to teach writing in the distance learning environment.

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Roger Billings Salute to Educators

“It was 50 years ago when I made the first Hydrogen Car. It is so gratifying to me to see this technology now beginning to be used all around the world. I am grateful to my teachers and educators that helped me to have the vision to dream an idea like this and the knowledge to put it on the street – to make it happen.” – Roger Billings

The Success Zone

To help students succeed, we created the “Student Success Zone” which is an education strategy that helps students succeed by getting into the right courses, at the right levels, so that they are able to  consistently progress. We call this being in their “Success Zone.”

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CybrSecurity Blog

By roger billings, serious cyber security solutions with, b² cryptography.

CybrSec specializes in Identity and Access Management for high-value military and enterprise operations in the cloud.   Visit the Blog »

Roger Billings Education Technology Insights COVER

Acellus: Promoting Coding Literacy with Cutting-Edge Technology

Education Technology Insights

“In the near future, Dr. Billings is kickstarting new projects like STEM-10 in an effort to have more graduates entering the STEM workforce with essential skills at a much higher pace… Dr. Billings’ sage advice to students is:  ‘Investing in learning and accumulating knowledge is going to pay you over and over throughout your life. Study hard. It will pay such a dividend throughout your career. You are worth the effort.'”

» Read More

The Art of Teaching Over the Internet

By Dr. Roger Billings, Chairman Acellus Learning System

Teaching students over the Internet is quite a different experience than teaching in the traditional classroom setting. When teacher and students are separated by a network, it is easy for students to feel ignored and adrift in their studies – as though no one is there to help them if they get stuck. This paper discusses these challenges and how to use the special learning resources Acellus provides to help the virtual teacher effectively teach at a distance.

» View Whitepaper

Acellus Learning Accelerator: Courseware Development Guide for Educators

In this book, Roger Billings shares the “secret sauce” which has made the Acellus Learning System a game changer for thousands of schools coast-to-coast. In these pages, the author shares the tools, the techniques, and the magic of Acellus that is changing education, discussing important aspects of the system.

» Look Inside

5 Reasons to Integrate STEM into Online Learning

By Roger Billings

Students need STEM–and a strong STEM learning background will carry them from high school to a high-tech workforce. As more and more fields require technical knowledge, it is a good idea to equip our young learners with basic STEM skills early on. With online schools, it is invaluable to start teaching these concepts at a young age, which is why STEM curriculum is now being introduced at the elementary level.


  1. Get Acellus Learning Accelerator for Your School

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  2. Acellus Learning Accelerator

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  3. Homeschool Program for School Districts

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  4. Rocky_Writing Tutor in Acellus

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  5. Roger Billings

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  6. Acellus Work Sample Tutorial

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  1. Acellus

  2. Presenting Traits and fossils

  3. Acellus “Congratulations!” lesson (English, 5th grade)


  1. Acellus Learning Accelerator

    The Acellus Writing Tutor ® is designed to tutor students as they write, giving immediate feedback on grammar, spelling, vocabulary, and even writing style. With this personalized feedback, students quickly discover that they can become exceptional writers.

  2. Get Acellus Learning Accelerator for Your School

    The Acellus Writing Tutor uses Intelligent Interaction to tutor students as they write, giving immediate feedback on grammar, spelling, vocabulary and even on the writing style. This is a long awaited game changer on our ability to teach writing in the distance learning environment. Watch Video.

  3. Acellus Learning Accelerator

    The Acellus Writing Tutor uses Intelligent Interaction to tutor students as they write, giving immediate feedback on grammar, spelling, vocabulary and even on the writing style. This is a long awaited game changer on our ability to teach writing in the distance learning environment.

  4. Online Homeschool Program (PreK-12)

    The all new Acellus® Writing Tutor is incorporated into student assessments to provide practice and feedback to elevate your student’s writing skills. Learn About Acellus Writing Tutor Prepare Your Student for a Career in STEM

  5. Roger Billings

    The Acellus Writing Tutor uses Intelligent Interaction to tutor students as they write, giving immediate feedback on grammar, spelling, vocabulary and even on the writing style. This is a long awaited game changer on our ability to teach writing in the distance learning environment.