In this 6-lesson unit, students use dominoes to explore four models of addition: counting, number line, sets, and balanced equations. They learn about the commutative property, the relation between addition and subtraction, the result of adding 0, and the concept of doubles. Students write story problems which involve the operation of addition and begin to memorize the addition facts. They represent addition in pictures. The various models of addition help students develop a rich conceptual schema for addition. Included are a Bibliography of Counting Books, student materials, questions for student and teacher reflection, assessment and extension ideas. [Suggestion: Use the alternate applet, Pan Balance - Numbers, listed as a Related Resource, rather than Pan Balance - Shapes, in Lesson 4.]

In this lesson plan from NCTM Illuminations students learn to add fractions with like and unlike denominators to make a sum of one. The lesson plan includes two games utilizing fraction cards (PDF) and a fraction bar chart (PDF), and an online game through Calculation Nation which is cataloged separately.

In this 7- lesson unit students use tallies, pictographs, bar graphs, line plots, circle graphs, box-and-whisker plots, and glyphs to collect and display data about healthy eating. The unit includes lessons in which two sets of data are being compared and data sets are being analyzed for measures of central tendency (mean, median, mode). Learning objectives, materials, student questions, extensions, teacher reflections, and links to create graphs virtually are included.

In this lesson, students are presented with a design challenge. Students make arrays to create options for package design for 24 eggs. Students work together to find the arrays and respond to the egg company.  

In this interactive activity a user identifies two pairs of equivalent fractions for a given random fraction or one of the player's own and the user creates their representations by dividing and shading either a square or circular region. The fractions are shown as locations on the number line and their equivalency is demonstrated when they are at the same point. The user has the ability to construct a table of equivalent fractions. Instructions and exploration questions are given.

In this math activity, learners are presented with a problem: two bowls are suspended from the ceiling by springs. One bowl is lower than the other. In one bowl, you can only place marbles; in the other bowl, you can only place bingo chips. Learners investigate how many items must be placed in each bowl so that the heights of the bowls are the same, and in doing so, solve a system of linear equations. This lesson guide includes questions for learners, assessment options, extensions, and reflection questions.

This Illuminations activity focuses on making predictions and the collection and analysis of data by having students take their pulse after different exercises. All individual data is collected in a classroom chart where the results are interpreted and conclusions drawn. The lesson includes a student worksheet and extension questions.

In this unit, students use online pan balances to study equality, order of operations, numerical and variable expressions, and other key algebraic concepts. Lessons focus on balancing shapes to study equality and equivalence; balancing algebraic understanding, to explore simplifying expressions; and balancing algebra, to determine if algebraic expressions are equal.

The rules of Krypto are amazingly simpleäóîcombine five numbers using the standard arithmetic operations to create a target number. Finding a solution to one of the more than 3 million possible combinations can be quite a challenge, but learners love it. This game helps to develop number sense, computational skill, and an understanding of the order of operations. Play this game online or use a deck of Krypto cards.

This lesson plan provides the teacher with an activity for introducing the game Krypto, which helps to develop number sense, computational skill, and an understanding of the order of operations. Players are given five number cards. They combine them, using the standard arithmetic operations, to create a target number. As students investigate the game, they develop strategies for finding solutions efficiently. The plan includes learning objectives, materials needed, questions to ask students, assessment options, extensions, teacher self-reflection questions, and a link to the online version, Primary Krypto, (catalogued separately).

In this math lesson, learners examine pennies and dimes and model subtraction as they listen to a childrenäóťs book ("Alexander Who Used to Be Rich Last Sunday" by Judith Viorst). Learners model amounts to 60 cents with coins, use coin rubbings of pennies and dimes, and make a chart comparing the two coins.

In this two-day lesson plan students collect, display, and analyze data about the eye color of their classmates. On day one, students display the eye color data in a pictograph and discuss what questions can and cannot be answered using this graph. On the second day of the lesson, data from a partner class is used to create a second pictograph. Students then compare these graphs and determine what questions can and cannot be answered using these two graphs. Questions and extension suggestions (including making a circle graph to represent data) are also included in the lesson plan.

In this lesson, students first create factor posters for a variety of different numbers that will be displayed in the classroom to be utilized as a resource throughout the school year. They make discoveries about factors using color tiles, represent their discoveries using graph paper, and display their information on poster board as find factors of an assigned number. The plan includes a list of materials, questions, assessment options, and extensions.

This is an interactive applet game exercises a student's factoring ability. A student can play against the computer or against a friend on grids containing the numbers 1-30, 1-49, or 1-100. Each player in turn chooses a number from the board, and then the opponent claims all of its remaining proper factors. A player's score is the sum of all the numbers and factors she/he has chosen. When there are no numbers remaining with unclaimed factors, the game ends and the player with the greater total is the winner.

An online, interactive, multimedia math investigation. The Factor Game engages students in a friendly contest in which winning strategies involve distinguishing between numbers with many factors and numbers with few factors. Students are then guided through an analysis of game strategies and introduced to the definitions of prime and composite numbers.

In this math game, learners identify the factors of a number to earn points. Although practicing a mundane skill, learners enjoy the work because of the game scenario. Built into this game is cooperative learning--learners check one another's work before points are awarded. This lesson guide includes questions for learners, assessment options, extensions, and reflection questions.

When students play the Factor Trail game, they have to identify the factors of a number to earn points. Built into this game is cooperative learning Š—” students check one another's work before points are awarded. The score sheet used for this game provides a built-in assessment tool that teachers can use to check their students' understanding.

This interactive applet allows a student to visually explore the concept of factors by creating different rectangular arrays for a number. The user constructs the array by clicking and dragging on a grid. The length and width of the array are factors of the number. A student can elect an option of a randomly selected number or the student selects his own number between 2 and 50. Exploration questions are included to promote student discovery of mathematical concepts with factors.

Through this four part lesson students develop an understanding of the relationship between area and perimeter. The lesson involves students making human rectangles, exploring geoboard connections, playing perimeter war, and playing Square Off from Calculation Nation. The lesson plan includes all data collection worksheets, games pieces, link to Calculation Nation, extension and assessment ideas.

In this primary grades Illuminations lesson, students identify figures on a football field. They look for both congruent and similar figures, and they consider figures that are the same but that occur in a different orientation because of translation, rotation, or reflection. The lesson includes a student worksheet and discussion questions.