In the following link you will find some free lesson plans sponsored by the Smithsonian Institute that relate directly to middle and high school horticulture as well as basic ag science curriculum. The lessons are called Nourishing the Planet in the 21st century and include handouts and activities you can use with your students in class.  The lesson also includes a pre-test and post-test for your convenience. - Scroll down to the middle of the page and click the link for Download Lesson Plans in the middle of the page

Here is a brief summary of the lesson included in the free download:

Lesson 1, In Search of Essential Nutrients - Students begin by comparing and contrasting the
nutritional needs of plants and people.

Lesson 2, Properties of Soils - They then explore soils and investigate how the components of soil affect
the movement of water in the soil .

Lesson 3, Plant-Soil Interactions - Students then turn their attention to plant anatomy. They explore
the role of the root system as well as that of the xylem and phloem tissues. They conduct a hands-on activity
that shows how nutrients move by diffusion.

Lesson 4, Plant Nutrient Deficiencies - They also consider how soil forms into layers called soil
horizons that have distinct compositions and functions.

Lesson 5, Fertilizers and the Environment - students consider what happens when plants do not
get adequate amounts of their essential nutrients. They play the role of plant doctor diagnosing the cause of
a nutrient deficiency. Students then consider the role of fertilizer in a global context. They investigate how
fertilizers can help feed people while protecting the environment. The consequences of misusing fertilizers
also are considered.

Lesson 6: Nourishing the Planet in the 21st Century - The module concludes with students reflecting
on what they have learned about plant biology, fertilizers, and fertilizers’ environmental effects in the context of
making recommendations for agricultural practices for the future

Trisha Rae Lastly 
South Region Agriculture Education 
Area Horticulture Teacher