Skip to content
Algebraic Thinking: Patterns and Equations · Weeks 19-27

Identifying Even and Odd Numbers

Investigating the properties of numbers that can be divided into two equal groups or pairs.

Key Questions

  1. What makes a number 'even' when looking at it as a collection of pairs?
  2. Why does adding two odd numbers always result in an even sum?
  3. How can we use rectangular arrays to prove a number is even?

Common Core State Standards

CCSS.Math.Content.2.OA.C.3
Grade: 2nd Grade
Subject: Mathematics
Unit: Algebraic Thinking: Patterns and Equations
Period: Weeks 19-27

About This Topic

Goods and services are the basic components of an economy. In this topic, students learn to distinguish between physical objects they can touch (goods) and work performed by others (services). This distinction is a key part of the C3 Framework's economic standards for early elementary grades. Students explore how both goods and services are essential for a community to function and thrive.

By identifying the goods and services in their own lives, students begin to understand the value of different types of work. This topic also introduces the idea of economic interdependence, how we rely on others to provide what we cannot make or do ourselves. Students grasp this concept faster through structured discussion and peer explanation, especially when they can categorize examples from their own neighborhood or school.

Active Learning Ideas

Watch Out for These Misconceptions

Common MisconceptionA service isn't 'real' because you don't get to keep anything.

What to Teach Instead

A service is valuable work that helps you, like a doctor making you feel better. Using a 'before and after' role-play (e.g., a messy room vs. a clean one) helps students see the tangible result of a service.

Common MisconceptionAll goods are food or toys.

What to Teach Instead

Goods include everything physical, from cars to pencils to houses. A 'mystery bag' activity with diverse items helps broaden their definition of what a 'good' can be.

Ready to teach this topic?

Generate a complete, classroom-ready active learning mission in seconds.

Frequently Asked Questions

Is a restaurant a good or a service?
It's both! The food you eat is a 'good,' but the chef cooking it and the waiter bringing it to you is a 'service.' This is a great example to show students that many businesses provide both to their customers.
How do people pay for services?
Just like goods, people pay for services with money. Sometimes we pay for a service one time (like a haircut), and sometimes we pay for it through taxes (like the police or fire department helping the whole community).
How can active learning help students understand goods and services?
Active learning, such as role-playing a marketplace, allows students to experience the exchange of value. When they have to 'sell' a service, they have to articulate the benefit of their work. This hands-on application helps them move beyond simple definitions to a functional understanding of how these two categories drive the economy.
What are some examples of services at school?
The teacher providing lessons, the janitor cleaning the halls, the bus driver taking kids home, and the librarian helping find books are all excellent examples of school-based services that students see every day.

Browse curriculum by country

AmericasUSCAMXCLCOBR
Asia & PacificINSGAU