KenKen is a puzzle game that helps students develop whole number calculation skills, logical thinking and perseverance. Users complete the interactive grid with the digits 1-4 (or 1-6) so that each digit appears exactly once in each row or column, while also forming a target number using a specific operation. This page provides four new KenKen puzzles daily with a range of difficulty. Each puzzle includes instructions, rules, and a print option.

The activities in this four-lesson unit enable students to use their knowledge of number, measurement, and geometry to solve interesting problems. Planning and visualizing, estimating and measuring, and testing and revising are components of the ladybug activities. Students design "virtual paths" that enable a ladybug to either hide under a leaf or go through a maze. They develop navigational skills by testing their path and revising it. Two interactive Java applets (Ladybug Mazes and Hiding Ladybug, cataloged separately) support student solutions.

This lesson introduces students to the measurable attribute of length and provides practice in measuring length using non-standard units. The lesson is launched using the story Ladybug on the Move by Richard Fowler. Lesson objectives, teaching ideas, and handouts are included.

In this unit of 8 lessons, students make groups of zero to 10 objects, learn number names for the groups, compose and decompose numbers, and practice writing numerals to record the size of a group. Each lesson includes visual, auditory, and kinesthetic activities and supporting materials, questions to facilitate student thinking and teacher reflection, assessment suggestions, and a link to online applets that support the unit.

In this 6-lesson unit students develop concepts of number, relationships between numbers, and equality. They make groups of 10 to 20 objects, connect number names to the groups, compose and decompose numbers, and use numerals to record the size of a group. Each lesson includes visual, auditory, and kinesthetic activities, as well as student activity sheets, questions for teachers and students, ideas for assessment and extensions, and links to electronic applets.

In this 5-lesson unit students make groups of zero through five objects and connect number words to the groups. They develop counting strategies and use numerals to record the size of a group. Lessons include familiar nursery rhymes and songs, links to interactive applets, and visual, auditory, and kinesthetic activities. Also included are student activity sheets, questions for students and teachers, assessment and extension ideas.

This 5-lesson unit is intended to help children who already understand the meanings of addition to develop fluency with addition facts. The activities and games take advantage of commutativity, the additive identity, doubles, and number patterns to develop operation sense and foster retention. Lessons include student materials, questions for students and teachers, assessment ideas, and links to interactive applets.

This sequence of four lessons is designed to help students to understand ratio, proportion, scale factor, and similarity. Using online activities, they compare the perimeter and area ratios of similar rectangles with various scale factors; work with scale factor and surface area of various rectangular prisms; explore the relationship between the volume of two similar rectangular prisms; and examine the connection between the surface area of two similar rectangular prisms. All instructions, needed links, and activity sheets are provided.

In this unit plan, primary learners explore the five models of subtraction (counting, sets, number line, balanced equations, and inverse of addition) using concrete (links), pictorial, and verbal representations to develop an understanding of symbolic notations. Students also investigate fact families, including those where one addend is 0 and where the addends are alike and also learn that the order (commutative) property) does not hold for subtraction. A brief bibliography of related books for children is provided. Instead of using hands on manipulatives and balances, links to Java applets: Pan Balance-Shapes and Pan Balance-Numbers ( both cataloged separately) are included. Instructional plan, questions for the students, assessment options, extensions,and teacher reflections are given for each lesson as well as links to down load all student resources.

In this math meets engineering activity, learners make paper airplanes and explore attributes related to increasing flight distances. Each learner collects data from three flights of the airplane and finds the median distance. Learners then collect, organize, display, and interpret the median distances for the group in a stem-and-leaf plot. This lesson guide includes questions for learners, assessment options, extensions, and reflection questions.

In this 6-lesson unit students use pasta shapes to explore the take away model of subtraction in several different contexts (counting, sets, number line, balanced equations, and inverse of addition). They decompose numbers, explore the zero property, act out subtraction situations with objects and pictures, record differences with vertical and in horizontal notation, create fact families, find differences with a calculator, and compose and solve problems involving subtraction. The lessons include student activity sheets (pdf), questions for student discussion and teacher reflection, assessment options, and links to online applets.

In this 5-lesson unit, students engage in measurement activities involving length, area, volume, time, and weight, using objects, pictures and symbols. Students practice measuring using standard and nonstandard units. Some lessons are introduced using children's literature.

In this lesson for grades 3, 4 and 5, students participate in activities in which they focus on patterns and relations that can be developed from the exploration of balance, mass, length of the mass arm, and the position of the fulcrum. The focus of this lesson is determining the position necessary to balance uneven objects and the effect on balance of moving the fulcrum. Printable activity sheets, ideas for implementation and extension are included.

In this math lesson, learners discover a powerful way to display dataäóîusing a glyph. Learners create glyphs by drawing their own faces on paper plates. Making a glyph involves the logical skill of classification--a learner must decide which groups he or she belongs to in order to complete the picture. This lesson guide includes questions for learners, assessment options, extensions, and reflection questions.

In this lesson students find and record addends that sum to ten in three different activities, using ten frames, linking cubes, two-sided counters, and a concentration game. The lesson includes suggestions for assessment and extension, reflection questions for students and teachers, links to related resources, and printable materials (pdf).

In this three-lesson unit, students participate in activities in which they focus on connections between mathematics and children’s literature. Three pieces of literature are used to teach geometry and measurement topics in the mathematics curriculum, i.e. using and describing geometric figures, estimating the volume of an irregular solid, and exploring the need for a standard unit of length. Activity worksheets and ideas for extension are included.

In this unit plan students apply their knowledge of data collection, display, and analysis to create a plan for improving the environment. Each of the four lessons in this unit requires students to collect data about recyclable materials and display the data for analysis. Each lesson includes students worksheets (PDF), discussion questions, and extension ideas.

In this math lesson, learners use yarn to measure lengths such as arm span and height. This gives learners practice measuring with nonstandard units. Pairs of learners also compare their height and arm spans. They practice problem-solving and reasoning skills by discussing why there are similarities and differences between the lengths of yarn that represent arm spans and height. This lesson guide includes questions for learners, assessment options, extensions, and reflection questions.

In this math lesson, learners measure distances using an outline cutout of their own feet. This enables learners to practice using nonstandard units. This activity is recommended as a follow up to the "Measuring with Teacher's Feet" lesson (see related resources). This lesson guide includes questions for learners, assessment options, extensions, and reflection questions.

In this series of three hands-on activities, students develop an understanding of the relationship between fractions, decimals, and percents based upon models of hundredths. Each activity requires students to display their one hundred pieces of candy in a different way: linear model, grid model (rectangular area), and region model (circle graph/pie chart). This lesson includes student worksheets, assessment questions, extension suggestions, and a link to a circle graph tool.