Tom Crilley

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February 27, 2018

Computer science: How To Teach It In Your Primary Classroom

This is the third installment of a three-part guest post series from Technology Integrationist Angie Kalthoff analyzing computer science in the K-12 education system. Read part one, Are We Too Late For Computer Science Education?, and part two, How To Teach Computer Science If You’re Not A Computer Scientist.

Computer Science_ How to Teach itand What to Consider-2.png

In 2017, I received a grant that supported our district's efforts to implement computational thinking in the K-5 classroom. In order to achieve a successful implementation, we needed to consider how our approach to computational thinking would complement:

Our team, consisting of teachers, media specialists and various other education professionals, created a scope and sequence for each grade level that incorporated both plugged and unplugged activities.

In this post, I will share with you lessons to take back to your classroom that we have found useful. To learn more about the grant, you can reach out to me on Twitter @mrskalthoff.

State standards and district curriculum
As a reference point, I’ve included state standards that we considered when developing our computational thinking lessons.

English language arts standards state that students should be able to:

  • Participate in collaborative conversations
  • Create individual or shared multimedia work for a specific purpose
  • Add drawings or other visual displays to descriptions to clarify ideas, thoughts and feelings
Mathematics standards state that students should be able to:
  • Solve and represent real-world and mathematical addition and subtraction problems
  • Understand how to interpret number sentences
  • Understand the relationship between the size of a unit of measurement and the number of units needed to measure
Computer Science Framework
We focused on the following concepts and subconcepts of the Computer Science Framework. Lessons are provided for each.

When students understand the relationship between algorithms and programs, they can take a list of instructions and encode it into a language. By the end of 2nd grade, the computer science framework states students should know that people follow and create processes as part of daily life. Many of these processes can be expressed as algorithms that computers can follow. Impacts of computing
Computing technology has positively and negatively changed the way people live and work. Computing devices can be used for entertainment and as productivity tools, and they can affect relationships and lifestyles. Debugging
Computing systems might not work as expected because of hardware or software problems. Clearly describing a problem is the first step toward finding a solution. Devices
People use computing devices to perform a variety of tasks accurately and quickly. Computing devices interpret and follow the instructions they are given literally.

Additional lessons can be found at

I would like to thank the wonderful group of classroom teachers, media specialists and various other education professionals that I was able to collaborate with on lesson creation and implementation.

Brenda Thielen, Sally Davidson, Lindsey Nagorski, Jodi Heinen, Cathy Bautch, Amy Jensen, Julie Nefs, Brandi Richards, Kelli Ritter, Ted Hanson, Pam Holubetz, Eric Maas

Media Specialists
Jenny McNew, Linda Hollenkamp, Jennifer Dahlstrom-Lage, Cole Bacon, Sara Martini, Jessica Moore, Holly Nelson, Paul Olsen

Amanda Anderson, Jason Menth, Jodie Kragness

University Partner
Diana Fenton

January 18, 2018

Everything you need to know about A Major New ClassHub Update

A major ClassHub update debuts a new user interface, improves performance, resolves issues and simplifies login and deployment.  

ClassHub Teacher
The Class Manager that teachers traditionally accessed through Reflector 2 now has its own dedicated application called ClassHub Teacher. ClassHub Teacher has all of the same great capabilities that were in Reflector 2 and more. This move eliminates confusion and creates a more seamless and improved ClassHub experience for teachers. 

Simplified login
The ClassHub login process is easier than ever. Students using Chrome OS devices never need to log in to ClassHub. All other devices only require students to log in one time. Students were previously required to log in to ClassHub every day or periodically. 

Administrators also have the ability to pre-assign students to devices. This preemptively helps teachers stage a classroom and accommodate changes to devices and class rosters. These login updates save time and minimize the possibility of user or technical error. 

A Windows update similar to the Chrome OS login update is in development. Upon release, students with Windows devices will never be required to log in, even on first use. 

The Class Manager contains a number of under-the-hood improvements that create faster performance for the end user.  

Additional updates

  • Resolved issue where newly enrolled Chrome OS students could still be required to log in once
  • Added a new platform filter for classroom app lock and app install 
  • Resolved an iOS app login issue when logging in to Clever with a Google account
  • Improved session handling to reduce occurrences of duplicate users and devices in a class
  • Restored logout/settings for users in certain ClassHub layouts
  • Restored Lock Application icon to Desk view when student is locked into an application
  • Fixed issues with the Configuration > General drop-down options
  • Enabled manually created school admins to properly select the schools they should administer
  • Added a more intuitive message than when enrollment codes expire
  • Resolved an issue with updating DEP profile configuration
  • Mirrored student devices automatically disconnect when a class ends
  • AirPlay/Cast Broadcast name automatically updates to <Teacher Name> - <Class Name> when class starts and back to default when class ends

Get ClassHub
ClassHub is a device management and monitoring solution that provides the tools needed to keep class on track, engaged and collaborative. 

Learn how to put ClassHub to work for your district today.

Schedule demo Learn more 


January 16, 2018

How to Teach Computer Science if You're Not a Computer Scientist

This is the second installment of a three-part guest post series from Technology Integrationist Angie Kalthoff analyzing computer science in the K-12 education system. Read part one: Are We Too Late For Computer Science Education?

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Stop me if you’ve heard this one before. 

“I can’t teach computer science because I’m not a computer scientist.”

That statement may seem valid, but it's inconsistent with our views on other subjects. 

Do you have to be a mathematician to teach math?

Or a published writer to teach someone how to write a sentence?

Or a historian to teach students about the Civil War?

Any teacher can incorporate computer science into curriculum. I’m going to tell you how.

Computational thinking

People always talk about how kids should learn how to code. Yes, but it’s more important to introduce computational thinking to students at an early age. Computational thinking is not coding or computer science. It’s important to know the difference.

In the simplest terms, computational thinking is taking big problems, breaking them down into smaller problems and solving them.

This excerpt from Digital Promise’s “Computational Thinking for a Computational World”  explains the differences.

“Coding is the practice of developing a set of instructions that a computer can understand and execute.

Computer science is the study of computers and algorithmic processes, including their principles, their hardware and software designs, their applications and their impact on society.

Computational thinking is ‘a way of solving problems, designing systems, and understanding human behavior that draws on concepts fundamental to computer science.’”

Computational thinking in the classroom

Look at the standards we are already teaching, then design learning experiences that tie in computational thinking concepts and approaches.

Don’t build lessons around a cool coding platform or fun robots. Build lessons around the ideas, and use the tools for hands-on investigative exploration.

You can categorize lessons in two ways:

  • Plugged
  • Unplugged

Plugged lessons
Plugged lessons require student access to a device like a laptop, Chromebook, iPad, tablet, etc. Many plugged lessons involve block-based coding platforms to help students learn computer science concepts., Kodable, Scratch JR and Scratch are a few of my favorites.

These resources allow students to collaborate on pair programing lessons. Pair programing in an app like Scratch JR teaches valuable computational thinking skills as students create programs for characters to move across the screen. Students learn to spot patterns and remove unneeded information (abstraction) as they evaluate the efficiency of their programs and fix mistakes (debugging) that occur.

Unplugged lessons
Unplugged lessons do not require students to access devices. Sites like CS Unplugged, Kodable’s lesson library and the unplugged lessons in’s CS Fundamentals help make real life connections around new concepts.

Computational thinking can be a foundational element of unplugged lessons.

For example, planting a seed or making paper airplanes teaches students about “real-life” algorithms. Have students learn programing by turning their friends into robots or teaching a robotic turtle how to access a jewel.

Challenge your students
Here’s a simple unplugged lesson that you can challenge your students to solve with computational thinking.

Suppose you have a friend with dirty hands. To help your friend, you need to:

  1. Decompose the problem (dirty hands = problem)
  2. Break down the steps required to successfully wash their hands by creating an algorithm for them to follow.

If the friend had never washed his or her hands before, you couldn’t simply say “wash your hands.” You would need to provide step-by-step instructions.

This lesson and others like it require children to think about the way they think. It’s an easy way to introduce the concept of computational thinking.

Stay tuned... 
In the third and final post in this series, I will dig deeper into lessons, share plans and provide valuable advice I've learned from my experiences working with teachers in the classroom. 

January 4, 2018

Squirrels LLC Verifies Largest Prime Number Ever Discovered

Squirrels built a supercomputer in 2015 to help find the largest and rarest prime numbers ever discovered. We're excited to announce today the discovery and verification of a prime number that's over 23 million digits long! 

The newly discovered prime number is 277,232,917-1. It's calculated by multiplying 77,232,917 twos together and subtracting one. 

This type of prime number, which takes the form 2P-1, is identified as a Mersenne prime. For example, while the smallest traditional prime numbers are 2, 3, 5, 7, etc., the smallest Mersenne primes are 3, 7, 31 and 127 calculated with P values of 2, 3, 5 and 7. 

Squirrels' supercomputer contributes computing power to the Great Internet Mersenne Prime Search (GIMPS). This search is a coordinated global effort that combines the power of thousands of computers to find the largest prime numbers ever discovered. 

Squirrels supercomputer

Squirrels was also one of the groups tasked with verifying the new prime number. This marks the second time the Squirrels supercomputer contributed to a Mersenne prime discovery. It previously helped verify a prime with more than 22 million digits in January 2016.

"We are happy that we are able to contribute not just to the prime search, but to many educational and research projects," Squirrels founder David Stanfill said. "I hope our contribution can help inspire the next generation of curious thinkers."

The next major GIMPS goal is to find the first 100 million-digit prime number. That one comes with a $150,000 award. 

How to get involved 
Anyone with a moderately powerful computer can download the free GIMPS software needed to contribute to the search and potentially earn money for new discoveries.

K-12 educators are bringing the prime number search to the classroom to get students excited about the power of mathematics and teach them about collaborative computing. 

Learn how to get started at

Learn More
Read the full GIMPS press release for complete details about the latest prime number discovery and user contributions.

Prime number.jpg

December 8, 2017

Are we too late for computer science education?

This is the first of a three-part guest post series from Angie Kalthoff, Technology Integrationist at a Minnesota public school district. In this series, Angie analyzes where the K12 education system stands with computer science education. 

Students often get their first dose of computer science education in high school. 

For many, that’s too late.

Studies show that if students are not exposed to computer science by fourth grade, stereotypes about people who are not good at science, technology, engineering and math (STEM) begin to form. These social stereotypes deter girls and students of color in particular from entering the computer science field.

This is a problem.

Computer science introduces critical literacies, such as coding, and skills that are fundamental to the development of college- and career-ready students in the 21st century.

How do we fix this?

We can provide earlier access and opportunities while highlighting self-efficacy in computer science. Students should begin learning computer science as early as kindergarten. That will help build a diverse computing landscape.

Introducing computer science in kindergarten will help prevent education stereotypes from forming during the time when students are curious, learning about the world and developing their interests.

Why not bring more technology experiences into our primary classrooms?

Based on a study of classroom teachers’ experiences, the primary motivation for teachers to use technology is the belief that technology will make them better educators and positively impact student learning. 

While most teachers believe that technology benefits students, few of them successfully integrate technology into their curriculum in a meaningful way. My colleague and friend, Diana Fenton, is working to change this by introducing her preservice teachers to technology integration best practices and computer science education early in their college experience.

Teachers who are not able to take Diana’s class can use the following resources for professional development opportunities:

Teachers who are currently in a classroom setting can follow the TPACK model for guidance on technology integration. By working together, we combine our skillset in the following areas: Technology, Pedagogy and Content Knowledge, which encompass TPACK. My district encourages this type of co-teaching.

Challenge yourself
I didn’t think that I could introduce computer science at the beginning of the school year when I was a kindergarten English language teacher. That’s an important time for developing relationships and establishing routines.

Then I challenged myself to think of how one of those routines could incorporate a computer science station in small group rotations. I saw the progress we made with computer science integration and decided to introduce it even earlier the following year to see what we could do with a whole school year.

Coming Up...
Stay tuned! In the second installment of this three-part series, I share how computer science lessons are integrated into our classrooms and how they connect with state standards, the ISTE Standards for Students and the CS Framework. 

To dive deeper into the research, visit the following resources:

Google. (2014). Women who choose computer science—what really matters: The critical role of exposure and encouragement.

Mountain View, CA: Author. Retrieved from

Huebner, G. (2017, April 20). Coding for Kids | 5 Reasons to Teach Kids to Code. Retrieved November 07, 2017, from

Ottenbreit-Leftwich, A. T., Glazewski, K. D., Newby, T. J., & Ertmer, P. A. (2010). Teacher value beliefs associated with using technology: Addressing professional and student needs. Computers & Education, 55(3), 1321-1335.

Young programmers -- think playgrounds, not playpens | Marina Bers | TEDxJackson [Advertisement]. (2015, January 20). Retrieved October 10, 2017, from

About Us

Squirrels is a software development company based in North Canton, Ohio. We create high-quality, budget-friendly screen mirroring and device management software that’s compatible with today’s most popular devices. To date, our software can be found in hundreds of thousands of classrooms, businesses and homes. Follow our blog for all the latest product updates, Squirrels news and technology insight!