# CONTACT CCSD21

Wheeling, Illinois 60090

Phone: 847-537-8270

Superintendent: Dr. Michael Connolly

# VISIT A SCHOOL

### CCSD21 is a school district comprised of 13 schools across 6 different communities in the northwest suburbs of Chicago.

VIEW BOUNDARY MAP

### BECOME A MEMBER OF THE SCHOOL DISTRICT 21 TEAM

School District 21 prides itself on its Professional Learning Community and its rich tradition of professional collaboration, high levels of professional development, and family-like atmosphere. If you see the opportunity to work with colleagues in making a difference in the lives of students and families in a truly diverse setting, School District 21 seeks your application.

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# Mathematics

## The Number System

### Power Standards

• Approximate irrational numbers (e.g., √2, ∏) to the nearest rational number. (8.NS.2)

### Concepts and Skills

* Power Standard Content

• * Rational numbers – terminating, repeating decimals
• * Irrational numbers – decimal approximations, number line locations

### Language Usage

• A student in 8th grade will demonstrate the ability to apply and comprehend critical language by explaining how to approximate irrational numbers to the nearest rational numbers.

### Content-Specific Vocabulary

• Rational
• Terminate
• Repeating decimal
• Irrational
• Decimal approximation

• Approximate

### Essential Understandings

• We classify numbers in our number system into a variety of categories to facilitate modeling and performing operations.

### Factual Guiding Questions

• How can you locate an irrational number on a number line?
• What is the difference between a rational and an irrational number?

### Conceptual Guiding Questions

• What does it mean for a number to be irrational?
• How can you determine whether a decimal is repeating, terminating, or non-terminating?

### Engaging/Debatable Guiding Questions

• Why do we sometimes approximate irrational numbers to rational numbers?