Pre-K-2
During this lesson, students practice addition facts (with sums of 5,
6, 7, and 8) in a concentration-game format using dominoes. Then they
generate sums to given numbers using a calculator and record them on a
hundreds chart and look for patterns.
Pre-K-2
Students sort foods using the categories of the Food Pyramid. They also create sets up to 10 and write numerals up to 10. Finally, students use an Internet-based tool to apply their knowledge of the Food Pyramid. This lesson makes a natural connection to the science of nutrition.
Pre-K-2
In this lesson, students make sets of a given number, explore relationships between numbers, and write numbers that name how many elements are in a group. They make and record sets of one more and one less than a given number.
Pre-K-2
In this lesson, students explore addition and comparison subtraction by modeling and recording related addition and subtraction facts for a given number. Comparison subtraction is the focus of this lesson because later in the unit, the students will explore the idea of "how many more?" to complete a set. The students also investigate the commutative property and model fact families, including those in which one addend is zero and those in which the addends are alike.
Pre-K-2
In this lesson, students explore the many ways to decompose numbers, and
they build on their knowledge of addition and subtraction to find
missing addends.
Pre-K-2
Students count back to compare plates of fish-shaped crackers, and then they record the comparison in vertical and horizontal format. They apply their skills of reasoning and problem solving during this lesson in several ways. [Because students have associated the word "more" with addition, the comparative approach to subtraction is typically more challenging for the students to understand.]
Pre-K-2
Students write subtraction problems, model them with sets of fish-shaped crackers, and communicate their findings in words and pictures. They record differences in words and in symbols. The additive identity is reviewed in the context of comparing equal sets.
Pre-K-2
In this lesson, students determine differences using the number line to compare lengths. Because this meaning is based on linear measurement, it is a distinctly different representation from the meanings presented in Lessons One and Two. At the end of the lesson, the students use reasoning and problem solving to predict differences and to answer puzzles involving subtraction.
Pre-K-2
This lesson encourages the students to explore another meaning for operations of subtraction, the balance. This meaning leads naturally into recording with equations. The students will imitate the action of a pan balance and record the modeled subtraction facts in equation form.
Pre-K-2
In this lesson, the relation of addition to subtraction is explored with fish-shaped crackers. The students search for related addition and subtraction facts for a given number and also investigate fact families when one addend or the difference is 0.
