What do you notice?   What do you wonder?

Make your own observations. Ask your own questions. Then click an image to learn more.


Welcome to 5280 Math, where teachers, parents, and teacher trainers find exciting, research-based, practical-to-use resources and tools to challenge and engage talented and adventurous math learners. The materials on this site are the result of over two decades of classroom experience teaching and learning with talented math students and nearly ten years supporting teachers in their work with these students. You can learn more about me and 5280 Math on the "About" page.

Adventurous math learners have two key qualities: curiosity and a willingness to take risks. At 5280 Math, adventurous students will find the perfect activities to feed their curiosity and deepen their understanding of math. For the remaining potentially adventurous students, the resources on this site will help to foster a new mathematical mindset of confidence, self-reliance, curiosity, and perseverance. Though the problems and activities are challenging, I hope that you will offer them to any student who wants to try them. They can be solved in many ways and often have multiple solutions. They develop mathematical creativity while still focusing on the content your students need to know. Students learn that the real goal is to stretch their thinking and learn new things, not to finish every problem or do it perfectly.

I hope you enjoy 5280 Math and find it helpful. Please contact me to let me know about your experiences with the resources. I welcome feedback and suggestions!

The ACCME Books

The Advanced Common Core Math Explorations series creates and nurtures mathematical adventurers! The books contain challenging, engaging activities that extend and deepen upper-elementary and middle school students' understanding of concepts from the Common Core State Standards in Mathematics. The investigations stretch students' mathematical imaginations to the limit as they ask questions, explore and extend patterns, and model real-world and mathematical situations. Each activity comes with extensive support for teachers including learning goals, discussion guides, detailed solutions (with multiple examples of student strategies), connections to algebra, and suggestions for extending the investigation.

This website contains an expanding collection of additional information and support for using the books, including descriptions of the activities, sample problems, personal comments, tips for teachers, extensions, and related resources.

What's New

Just arrived in March 2017!

Advanced Common Core Math Explorations: Probability and Statistics, published by Prufrock Press


The sixth book in the ACCME series for upper elementary and middle school students has just arrived! It is loaded with challenging and engaging real-world projects. LIke the previous book on ratios, proportions, and similarity, Probability and Statistics uses a format inspired by Ian Byrd of byrdseed.tv. The problems have been separated onto individual pages with streamlined, bulleted directions. Each problem is introduced with a "teaser" that encourages students to come up with their own questions and observations before receiving the directions. The discussion guides have been rewritten as "I notice" statements and "I wonder" questions. The look and feel of the pages is open and inviting, and the writing is more conversational. The new format enhances the open-ended, inquiry-based nature of the problems. Incidentally, Ian has created wonderful videos for three of the activities in the ACCME. I hope you will check them out at his website!

Noticing and Wondering in the Classroom

What do you notice?   What do you wonder?

Make your own observations. Ask your own questions. Then click an image to learn more.

Featured Resources

The Number Devil

The Number Devil
Hans Magnus Enzensberger
Metropolitan Books, 1997

The Number Devil, by Hans Magnus Enzensberger, has been a favorite book of my students and of mine for many years. It is the story of twelve-year-old Robert and an irascible, math-loving devil whom he dreams about when he goes to sleep each night. The Number Devil takes Robert on mathematical and historical journeys through large and small numbers, the Pascal triangle, Fibonacci patterns, factorials, triangular numbers, networks and nets, logic, Klein bottles, and more. Robert is skeptical at first, because his math classes have always been about memorizing rules and solving meaningless problems. But, in the end, the Number Devil wins him over, and Robert discovers his own inner mathematician. Illustrations by Rotraut Susanne Berner bring the mathematics and the cantankerous devil to life. Whenever I share this book with students, the school media centers order multiple copies to ensure that they have enough on hand to meet demand. The Number Devil is a colorful, amusing, and enlightening mathematical treat.  --JB


from 5280 Math: Monthly Problem Sets

Are you looking for challenging problems that are connected to math content standards and do not require a lot of direct instruction? I am currently developing a collection of Monthly Problem Sets for grades 4,  5, and 6, and I would appreciate your input. Each set will contain problems from the different strands: Number and Operations, Algebra, Geometry and Measurement, Measurement and Data, and Probability and Statistics. There may also be some problems related to general mathematical topics. 

                 Grade 5 September Problems

The grade 5 problem sets are now complete.  Grades 4 and 6 are in progress. Of course, you may use the sets at any time—not just during the specified month. I am currently testing the problem sets out, so please let me know how they work for you and how you implement them in your classroom.  If you find errors or have suggestions, I would appreciate hearing your ideas!