In late 1999, Kay Emerson founded the Evan McKenna Foundation, named after her children, as a 501(c) (3) non-profit as a way to give back to the community, with the primary focus being on education. After a few small projects in both reading and math, she narrowed the focus to math education, because math is difficult and demoralizing for the majority of American children. Over time she further refined the mission to become:

The Foundation is dedicated to providing parents, teachers, and other educators with engaging tools and innovative teaching strategies to deepen elementary school students’ number sense, pattern recognition, reasoning, and problem solving skills to help them succeed in middle school math and beyond.

Prior to creating the Foundation, Kay worked in both private industry (Hewlett Packard, Coopers & Lybrand, small software startups) and the public sector (the City and County of San Francisco, and the Florida Department of Transportation) in finance and administration. She taught courses at the university level in accounting and decision sciences and was an active volunteer in public schools in classrooms, curriculum committees and special education. She has a BS in Engineering in Computer Science from Vanderbilt University and an MBA from the University of Hawaii. A small part of her studies were in artificial intelligence and game theory. which she enjoys bringing to bear in Zillio games. She is a CPA (inactive).

After founding what has become Zillio, Inc and the Zillio Foundation, she has worked with hundreds of teachers and thousands of students to constantly identify new tools, techniques, and activities to meet the needs of those involved in math education.

"When I was a parent of elementary school children, I realized that my children and most of their classmates were not developing mental images of critical math concepts and how they relate to one another. I invented and developed Zillio to provide children with a fun and powerful way to see, touch, and understand essential math concepts. The goal was to make serious math fun and accessible to all learners as they prepare for a successful math experience in middle school and beyond.

Zillio (formerly NICSI Mountain) is the result of a wonderful collaboration between teachers, students, math professionals, school administrators, parents, industrial designers, website developers, manufacturers, and other business professionals. Many individuals and companies gave generously of their time and expertise to bring the idea to life. We are always looking for new contributors. Please contact us." Kay Emerson, Founder

Zillio Mountains and the 2D Playground provide the foundation for exploration

Zillio provides a constant frame of reference for numbers in a fixed relationship so that students see and understand the organization of numbers as they explore particular problems. Patterns are readily identifiable because many examples can be displayed simultaneously. This visual presentation of multiplicative reasoning and equivalency provides the foundation upon which more advanced instruction and problem solving is built. Being able to move fluidly from one concept to another (for example from multiplication to number lines to fractions) accelerates learners ability to make connections between math concepts and develop both the fluency and flexibility necessary to support problem solving.

Lessons in a Variable Format

In completing most tasks, students are working independently, but in parallel. Students begin to understand the “learn once, use many” aspect of most mathematical operations. Each student can see that everyone is using the same algorithm even though he/she and his/her neighbors are working on different problems. Not only does this approach make lessons more engaging and abstraction easier, but it also builds confidence.

Deployment of Algebraic Concepts Earlier

Some advanced algebraic concepts & skills such as factoring, common multiples, and equivalent fractions can be developed at an earlier age, because children can easily see and understand them. This enables students to use algebraic thinking to support them in problem solving where memory alone may not be sufficient.

Thoughtful Pattern Recognition Built into the Assignments

Worksheets are structured to emphasize and help students apply pattern recognition skills to move fluidly from whole numbers to fractions, constants to variables, and straight-forward problems to more complex ones. Students feel less intimidated when these advanced skills are merely an extension of the same algorithm and reasoning.

Highly Engaged Students

A range of skills can be used to complete the tasks and the activities and setup are conducted so that pace of one student rarely negatively impacts the pace of another. Each student remains more fully engaged and for a longer period of time while they master skills appropriate to his/her current stage of development. All students are solving problems and learning.

Risk Taking Environment & Students Who Have Difficulty With Math

In many ways Zillio is an opportunity for learners to redefine their capabilities to succeed in math. During the hands on activities there are no written records of mistakes and huge incentives to try. Students understand concepts once out of their reach. They develop fluency in key algorithms and skills. They accomplish more than they thought possible and begin to believe in their ability to succeed.

The word "activities" is used to encompass games and lessons. Both are fun math-rich hands-on exercises. Click on the Hands-on Activities page for a description of key differences between games and lessons.

To develop the games and lessons, we start with a state or national standard. We then created visual and kinesthetic approaches to develop fluency, conceptual understanding, and problem solving & reasoning skills to ensure students’ success. We then embedded these techniques in 80+ math rich but fun-filled games and activities. Most activities have worksheets that can be assigned to help children transition skills learned on the Mountains and 2D Playground to paper using traditional representations.

Yes, most lessons have written assignments that can be used to assess students’ understanding and provide data to inform instruction, but one of the best ways to assess is by observing students during the games themselves. You have ample opportunity to see the students’ conceptual understanding, fluency, problem solving and reasoning skills in use.

Usually two to five minutes is all that is required to set up the activities and often students do the setup to develop fluency in a particular skill. 
If you are working with more than one group of students you can often leave the activity set up after the first group has finished to cycle through all groups faster.

Yes, although many lessons and games require small groups, often you can have multiple small groups working on multiple Mountains of 2D Playgrounds at a time. In addition, 2D worksheets allow you to work with the whole class to reinforce or sometimes introduce key concepts.
When you are teaching a new skill for the first time, you may need an additional assistant (math coach, upper grade student, aide, or volunteer) to conduct whole class activities. Also Zillio activities and games are wonderful projects to do using your buddies in a upper or lower grade.

When you get your Mountain, spend some time exploring it and reading the Quick Start guide before you begin with children. If you have questions please call us and we can do a quick walk through with you. When you introduce it to children, allow them some time to explore and investigate on their own. When selecting the first game, watch the skills they use during setup and then pick an easy game that will allow them to succeed and have fun.
Click here to see a tutorial on Getting started on Mega & Mini

We created a paper version of the Mountains. Similar to graph paper, each row represents an elevation and each column represents a staircase. The steps are colored at appropriate intervals to mirror the Mountain. Children can use these to practice fluency and problem solve. They help in the transition to traditional algebraic representations and are sometimes even easier to understand a concept. We have developed several different worksheets to use to achieve different practice goals. They are included in the instructions for activities where appropriate and a complete set of reproducible 2D worksheets can be downloaded from our Resource section. Click here to see a tutorial on 2D Worksheets.

Both 36 and 60 have at least 6 factors. This is important in many of the games and allows you to explore at many equivalent fractions on each Mountain.




Mega Zillio comes out of the box all set up and ready to go. We recommend that you treat Mega Zillio as a permanent fixture in the classroom so that children have a visual reference. If you wish, you can return Zillio Mountain to its box when not in use. The box measures approximately 27" by 27" by 12" and can be stored on its side.
Click here to see tutorial getting started on mega

The Mini Mountain has a nice new feature. The top of the Treasure trove screws on to hold the staircases in place when the Mountain is not in use. It is lightweight enough that it can even be hung on the wall.
Click here to see tutorial getting started on mini

Yes, the Mountains can support hundreds of pounds of weight. This load was not a design criterion, but it does give you an idea of how sturdy it is. Also, we do realize that classroom materials are not always used by the students in the manner intended. Use on the floor may require more supervision than use on a desktop.


Hand wash in warm water, using a mild soap for dishes.


They weigh 11 lbs. and 26 lbs., respectively.


The 2D playground can be used as a game board, a worksheet, or a poster. It is a nice addition to the Mountains because the top view presents the relationships between numbers in a different way.
Click here to see tutorial on 2D playground

The tokens are easy to store. Just put them back into the foam card after every use. You can place them in number side up in numerical order, or just place them in the foam card any place blank side up. That way you will know they are all accounted for but that they have not yet been put in the correct sequential order. While you are putting the tokens away you have a good to opportunity to discuss what participants may learned or practiced during the activity.
Click here to see tutorial on more about tokens

Of course. A set of foam cards is inexpensive. Please visit our store or send us an email to purchase more.

We recently changed token sizes so they fit more snuggly. You can now picking up a staircase with tokens in place and even turn it up side down without tokens losing their place. All mountains now ship with new tokens. If you have an older set, visit our store to purchase new ones – you’ll be glad you did. Measures 1.3 cm wide by 1 cm deep by .5 cm high.

Think about your objectives. Do you want to practice skills with which they are already familiar? Do you want to provide incentive for developing a new skill?

Think about the group of youngsters. Do you want to play a competitive version or a collaborative version? Do you need a game so youngsters of various ages and skills can play? Are they ready for strategic games?

Then go either to our games index page to select by age or our activities index page to select by grade level and skill, and browse through the choices. Note: The activities index includes lessons as well as games. The title of the activity will give you a hint as to whether it is a game or not.

View our game tutorials on the resource page to learn how to pick the right games.

Yes, a number of games are in development, including some deluxe games with special pieces, cards, etc. Please email us requests for additional themes, skills, etc. or even better submit instructions for games you have created and we’ll post the winner each quarter on our blog.

In most cases the games are played in a similar manner. In the educator's version we also include hints on what to observe and discuss, and include worksheets that can be used to reinforce skills.

By all means just let children play and explore on their own. Many times that is the best way to introduce the Mountains. Children will be able to make meaning on their own. Those of you who are constructionists will want to continue to approach learning on the Mountains/Playgrounds as investigations rather than formal lessons and demonstrations.

Also don't be surprised if children incorporate the Mountain into their other play activities. It can be a wonderful stage, prop, or set for all kinds of imaginative play.