This intereactive Flash applet helps children learn grouping, tally marks, place value, addition, and subtraction. Students help the alien spaceship move cows into corrals by counting by 5s and 10s. They also can apply those grouping skills to practice adding and subtracting two-digit numbers with regrouping. Audio cues and prompts reinforce the user's actions and facilitate counting and the development of math language.

This lesson, from Illuminations, gives students practice in measurement and in displaying and interpreting data through box-and-whisker plots. Students may draw the plots themselves or use the online Box Plotter tool. Learning objectives, materials, student questions, extensions, teacher reflections, and NCTM Standards alignment are provided.

In this math lesson, learners read the book "How Big Is a Foot?" by Rolf Myller. Then, learners create non-standard units (using their own footprints) and use the footprints to make "beds." As a result, learners explore the need for a standard unit of measure. This lesson guide includes questions for learners, assessment options, extensions, and reflection questions.

In this math lesson, learners read the book "How Big Is a Foot?" by Rolf Myller to explore the need for a standard unit of measure. Students then create non-standard units (using their own footprints) and use the footprints to make "beds." This lesson guide includes a student activity sheet, questions for learners, assessment options, extensions, and reflection questions.

This lesson emphasizes the connections between science and mathematics by using a performance, or authentic, assessment format. Students will develop measurement skills as they relate the size of their fists to the size of their hearts. Students have the opportunity to explore applications involving their own hearts. An activity sheet (pdf) is included.

In this lesson, students measure the dimensions of their own fist plus the fists of some other people who are older to approximate the size of each person's heart. Next they use construction paper to make a model of their own heart.

In this lesson, students use historical nonstandard units (digits, hand, cubit, yard, foot, pace, fathom) to estimate the lengths of common objects and then measure using modern standard units. They will discover the usefulness of standardized measurement units and tools. An activity sheet (pdf), assessment options and other commentary are provided.

The activities in this 6-lesson unit use fish-shaped crackers to help students develop their understanding of comparative subtraction by exploring five meanings of subtraction (counting, sets, number line, balance, and inverse of addition). Students investigate properties of subtraction, represent subtraction with objects and pictures, record subtraction with vertical notation and equations, create and solve problems, and carry out missing addend activities. Lessons include questions for student discussion and teacher reflection, extensions, printable student sheets, assessment options, and links to online applets.

In this lesson activity students use nonstandard units (baby steps) to measure lengths of different types of "steps" (giant, regular, umbrella, scissor, wooden-soldier, and backwards steps). Once each student gathers this data they will display their own data on a bar graph. Then the class will discuss the data and compare graphs among students. A students worksheet for data collection is included in PDF format.

This activity has students explore the patterns that emerge when connecting midpoints of triangles. The activity includes a student worksheet, discussion questions, and an interactive fractal tool.

This interactive Flash applet helps students develop number sense and fluency with addition and subtraction facts within 10. Okta hides some bubbles under a shell, and then either adds more bubbles or takes some away. Students determine how many bubbles are left under the shell. Users can choose a specific one-digit starting number or let the applet choose randomly. Users can select addition, subtraction or both.

This lesson focuses learners on the concept of 1,000,000. It allows learners to see firsthand the sheer size of 1 million, while at the same time providing learners with an introduction to sampling and its use in mathematics. Learners use grains of rice and a balance to figure out the approximate volume and weight of 1,000,000 grains of rice. This lesson guide includes questions for learners, assessment options, extensions, and reflection questions.

In this recycling activity students conduct a poll and display data showing which type of material the survey population feels is the best for shopping bags. Students share their results in a data display of their choice and then use the data to draw conclusions and create a recycling plan. The activity includes the student worksheet, extension suggestions, and related resources.

This 2-lesson unit focuses on combinations, a subject related to probability. Students develop strategies for discovering all the possible combinations in two given situations. They learn to collect and organize data and then use the results to generalize methods for determining possible combinations. They discuss how the number of possible outcomes is affected by decisions about the order of choices, or whether choices may be repeated. The unit includes student activity sheets, questions and extensions for students, and a link to an interactive applet.

The applets in this Interactive Geometry Dictionary (IGD) will allow students an opportunity to explore finding the area of some common shapes. The applets demonstrate how to find the area of a triangle using the area of a parallelogram, which in turn can be found using the area of a rectangle. This tool also supports the lesson "What's My Area" cataloged separately.

In this lesson students are introduced to various types of symmetry. After exploring the symmetries that exist with letters of the alphabet, they make inversions of their own name. Suggestions for implementation and support materials are provided.

In this lesson plan from Illuminations, students use relationship rods to explore fraction relationships. Relationship rods range in length from one to ten centimeters, and each rod is a different color. An activity sheet with solutions, questions for students, assessment options, and suggested extension activities are included. The lesson plan is part of a five lesson plan unit, Fun with Fractions, which is cataloged separately.

This Java interactive tool can be used to create dynamic drawings on an isometric dot grid, and to explore volume, surface area, and congruence concepts. Users can draw figures using edges, faces, or cubes and can shift, rotate, color, decompose, and view figures in 2‑D or 3‑D with this applet. Instructions on using and exploring with the tool are included on the page. A related multi-lesson unit from Illuminations for middle school students is linked to the side.

This lesson plan combines physical activity (jumping jacks) with data collection. The purpose of this activity is to compare and contrast the use of mean, median, and mode as the best measure of central tendency. The lesson plan includes three worksheets, extension questions, and assessment options.

In this math activity, learners prepare jumping jack data to send to officials on the planet Jumpalot. Learners record how many jumping jacks they can do in ten seconds and use their knowledge of time conversions to figure out how many jumping jacks they could complete in a minute all the way to a year. Learners then organize group data and explore mean, median, and mode and the effects extreme values have on these measures. Finally, learners brainstorm the advantages and disadvantages each measure offers. This lesson guide includes questions for learners, assessment options, extensions, and reflection questions.