Click here to view the lesson plan (pdf).

Grade: K to 2

Introduction

The term weed describes any plant that is unwanted where it is growing, is difficult to eliminate, and has the ability to spread. A plant may be considered a weed in one area, but not another. A flower in the middle of a playing field and grass growing in a flowerbed may each be considered a weed. Students will acquire a rudimentary understanding of weeds.

For best results, conduct the Activity in late spring or early summer, before the lawn has been mowed. Before teaching this lesson, read the entire lesson and make sure all materials are available.

Click here to view the lesson plan (pdf).

Grade: K to 2

Introduction

By observing plants in a natural setting, students will learn important concepts about invasive plants. The weed scavenger hunt provides an opportunity for teachers to introduce and discuss the following concepts: native and non-native plants; adaptations, including seed dispersal mechanisms, defenses against herbivores, water conservation and drought tolerance, allelopathy, and adaptations for attracting pollinators; food chain; ecosystem; and mono-culture. Before teaching this lesson, read the entire lesson and make sure all materials are available.

Click here to view the lesson plan (pdf).

Grade: 3 to 5

Introduction

The Activity in this lesson introduces students to the concept of an ecosystem. Change in plant communities over time is difficult for students to observe or comprehend because plants usually grow slowly. By manipulating a simple interactive model that simulates an ecosystem, students will learn about destabilization and rapid change that occurs when a non-native plant species invades an area. Manipulating the model will accelerate the process of change. Through observation, students will gain an overview of how changes, especially the introduction of a non-native plant species, can affect an ecosystem. Use this lesson to prepare students for field studies that involve exploring actual ecosystems. Before teaching this lesson, read the entire lesson and make sure all materials are available.

Click here to view the lesson plan (pdf).

Grade: 3 to 5

Introduction

Exotic weed species are those that originate in other countries. Many exotic weed species exist in North America. The natural checks and balances that keep these species under control in the environment in which they evolved are not present in our country. Once they have been introduced, exotic species out-compete native plants by stealing the moisture, nutrients, and sunlight that native plants use. Areas in which the soil and plant communities have been disturbed are the most vulnerable to invasion by exotic species. From an ecological viewpoint, invasive weeds are a pioneer species.

Natural plant communities are altered when native species are eliminated. These alterations are often a detriment to many other organisms, including humans. Weeds are a costly problem for rangelands and crops.

Using photos of themselves and plants, students will learn about how plants and their seeds travel great distances. Students will discuss adaptations that enable plants to survive in a new environment. Before teaching this lesson, read the entire lesson and make sure all materials are available.

Click here to view the lesson plan (pdf).

Grade: 3 to 5

Introduction

Students will learn about some of the adaptive characteristics of invasive plant species. These adaptive characteristics enable plants to out-compete native and crop species where soils have been disturbed. Using a simulation activity, students will acquire an understanding of the concept of competition among species and the ecological consequences of competition. Students will apply their knowledge to create imaginary species that are ideally suited for invading an area.

During Preparation, students will participate in a race to learn about competition. Before teaching this lesson, read the entire lesson, decide what the race will be about, and make sure all materials are available.