Make S'mores from a Solar Oven

About the Experiment

Solar ovens are used around the world as an economical and efficient way to cook food. Solar ovens do not need electricity or gas, and they can be mobile for easy transportation. A solar oven works by capturing the sun’s light and turning it into heat. The shiny foil reflects extra sunlight into the box, increasing the amount of energy that enters. The black paper absorbs that energy and warms up because dark colors soak up more light. The clear cover acts like a greenhouse: it lets sunlight in but slows down how fast the heat can escape. Together, these parts create a sun-powered heating system that shows how solar energy can be collected and used to cook food.

Details

Ages: 6+ | Time: 1 hour  | Difficulty: Easy

What You Will Need

• 1 clean, medium to large pizza box or shallow cardboard box with a lid

• Aluminum foil

• Black construction paper

• Scissors and tape

• A stick or pencil, to hold the lid open

• Clear glass panel or a large clear bowl (to trap heat)

• Ingredients for S’mores

Safety Note: This experiment must be done with the assistance of a parent or adult.

Let's Do This!

1. Prepare the Box

   • Open the pizza box.

   • Line the bottom of the box with black construction paper.

   • Tape it down flat.
      

2. Make the Reflector

   • Cover the inside of the lid with aluminum foil.

   • Keep the shiny side facing out.

   • Tape the foil so it's smooth
      

3. Add the Window

   • Since we’re not using plastic wrap, place a clear glass panel or a clear bowl over the food inside the box.

   • This works like the “window” to trap heat.
      

4. Set Up the Oven

   • Build your S’mores and put them in the center of the black paper or make and wrap them in foil.

   • Close the lid gently.

   • Prop open the lid using a stick or pencil so sunlight reflects inside.
      

5. Cook with the Sun

   • Set the oven in direct sunlight.

   • Adjust the foil reflector to shine light inside the box.

   • Check every 10 minutes. S’mores usually take 10–20 minutes!

   • Be careful when removing the S’mores from the oven.

   • Use oven mitts if necessary.

Observations

• Add a temperature gauge and determine how hot the oven got inside. How hot did you get the oven?

• What would happen if we tried the experiment on a cloudy day?

• What time of day did you try this experiment? Would it matter if you did the experiment in the morning vs later in the day?

• What did you notice about how the marshmallow changed during the experiment?

• Why do you think the chocolate melted in the solar oven?

• What other food items would be ideal for cooking in a solar oven?

Download the printable "Make S'mores from a Solar Oven" project PDF: 

Nurturing the Next Generation of Agricultural Scientists

ARS Scientists are hosting six LEADing NexGen interns at the Fort Keogh Livestock and Range Research Laboratory, in Miles City, MT. 

The students hail from land-grant institutions including Texas A&M at Kingsville, TX, and New Mexico State University in Las Cruces, NM. As interns, they will gain a unique opportunity to obtain hands-on experience in livestock production management. 

Over the 10-week program that runs through early August, ARS scientists are leading the interns through next generation practices in livestock management. Their instruction includes branding, pasture utilization, artificial insemination and natural breeding programs. Students will also learn about post-partum supplementation (the role of strategic supplementation), and the data collection and analysis (for blood metabolites, DNA for sire confirmation, and rumen digestion). In addition, they will gain an understanding about the proper techniques used for blood collection and milk-production sampling. 

“Through the strong partnership between USDA-ARS and our university collaborators, the interns are immersed in hands-on research and real-world livestock production practices,” said Dr. Richard Waterman, ARS animal scientist who supervised the internship program.

During the summer program, the interns also have the opportunity to identify common management issues related to range livestock production. Using scientific literature, they will lead discussions for the Fort Keogh professional research team on those issues. 

“The students’ dedication, curiosity, and professionalism have shined in every task they performed,” he added. “They are giving us an inspiring glimpse into the future of our industry. We are grateful for the expertise, energy, and fresh perspectives they are bringing to Fort Keogh throughout this summer.” --Tami Terella-Faram, ARS Office of Communications

Crumb and Get It! 

Hard wheat flour is a much-kneaded ingredient for bread. Hard wheat is preferred when baking bread as its high levels of gluten helps dough rise. Hard wheat has fiber, vitamins, and high protein – making it a more heart healthy choice. 

ARS researchers from the Plant Science Research Unit in Raleigh, NC, have developed hard wheat lines that produce flour for bakers to use in their breads. These wheat lines can resist diseases and produce high yields, important traits for our American wheat farmers.  

While it is important for wheat to be healthy and strong, bakers also want wheat that makes toast-fully yummy bread. A lot goes into making a loaf, and bakers take their craft seriously. Some qualities bakers look for in breads are appearance, crust, color, texture, aroma, flavor profile, mouth feel, and crumb appearance.  Who knew there are so many qualities to look for in bread?

To put their work to the test, ARS researchers crumbed together”  with bakers in North Carolina to taste different breads made with flour from ARS wheat lines. They scored the different breads and found that these breads had the flour power to rise to the occasion for baking delicious breads. Talk about some real breadwinners! 

This is an example of how research done by ARS goes from field to flavor and how science plays a role in making foods we eat each day! Click here to learn more.

Protecting America’s Forests from a Devastating Disease

Beech leaf disease (BLD) is killing forest trees across the United States. Caused by the nematode Litylenchus crenatae , the disease was first detected in the United States in Ohio in 2012 and has spread to at least 15 other states, from Maine to Virginia to Michigan. It was also recently discovered in the Canadian province of Ontario.

Beech tree saplings infected with BLD usually die within 5 years of infection. Mature trees can take several years to die of the infection. Early detection is key for managing tree devastation in forests. However, diagnosing BLD in trees can be difficult, as it currently relies on visually identifying the distinctive dark banding that forms between leaf veins, which is not possible at certain tree heights or at early stages. Although artificial intelligence (AI) has been increasingly used to support plant disease identification, no AI-based system had previously been developed for detecting BLD from images. 

ARS researchers Benjamin Waldo and Paulo Vieira at the Mycology and Nematology Genetic Diversity and Biology Laboratory trained a machine learning model capable of identifying BLD in real-world images with over 95% accuracy. This work provides an important step toward a more comprehensive BLD detection system and establishes a foundation for future image-based diagnostics of foliar nematode diseases. This innovative technology will assist tree and forest health professionals in rapidly identifying the presence of BLD and enhancing their ability to control the spread of this devastating tree disease.

For more information:

• https://scientificdiscoveries.ars.usda.gov/tellus/stories/articles/hunting-tree-killer 

Science Behind Your Cookout

From burgers to beer to bug spray, ARS scientists contribute to many of our July 4th favorites. ARS research keeps food safe, improves crops like potatoes and hops, and has led to repellents from DEET to newer plant‑based options. ARS innovations quietly shape the food you eat and the way you celebrate—making your holiday food safer, tastier, and more sustainable. Click here to learn more.

Special Pit Stops for Nature’s Little Helpers

Monarch butterflies are not only beautiful insects, but also a vital part of nature. Among their many talents, they spread pollen, which helps plants grow fruits, seeds, and new flowers. This is important for farmers because healthy plants mean more available food for people and animals.

During the course of a year, Monarch butterflies travel as far as 6,000 miles back and forth from Canada to Mexico. That’s a lot of frequent flyer miles!

To help monarch butterflies survive their long journey across North America, many communities have created Monarch Waystations. These special gardens provide the two things that monarchs need most: milkweed plants for their caterpillars to eat and nectar flowers for adult butterflies to drink from. Because monarchs travel thousands of miles during their migration, they need safe places to rest and refuel along the way—like tiny butterfly pit stops!

Did you know that you can support these little helpers by creating safe spaces for them to get food and water? The USDA Future Scientists Program helps us understand how to support these beautiful butterflies and other pollinators by creating “pit stops” for their journeys. High school students, for example, helped create such a space in the inner quadrangle at the ARS San Joaquin Valley Agricultural Sciences Center in Parlier, CA. 

You too can support farms by creating a Monarch Waystation. It can be as small as a patio pot planted with milkweed and other pollinator plants.

If you are interested in creating a Waystation at your home, school, or local community, check out the Monarch Waystation Program and learn how you can make a garden for these special travelers. By building a Waystation, you can help protect these amazing insects and support their incredible migration year after year.

###

A Balanced Diet for Honey Bees 

Honey bees understand the importance of a balanced diet. 

ARS and Texas A&M University researchers observed how nurse bees, who are tasked with feeding developing larvae, regulate their protein-lipid (fats) intake in an experimental study using diets that mimicked pollen. 

“Our study shows that nurse bees favored diets containing 30% protein and 20% lipids,” said Pierre Lau, a research ecologist at the ARS Pollinator Health in Southern Crop Ecosystems Research Unit in Stoneville, MS. 

Lau added that nurse bees generally regulate this protein-to-lipid ratio when given a choice between imbalanced diets. According to Lau, this finding showed that bees, like humans, need a balance of proteins and lipids to maintain good health. 

Want to learn more? Read Balance is Key for Nurse Honey Bees’ Diets. 

###

Meet the Chimney Bee: A Promising Pollinator for Fruit Crops

As honeybee populations ebb and flow, ARS researchers are turning to native chimney bees to help pollinate crops like blueberries. These gentle, low‑maintenance bees can be relocated, build nests from clay “chimneys,” and excel at pollinating plants that honeybees often overlook. While not yet commercially available, chimney bees show strong potential to boost fruit yields and fill critical pollination gaps—supporting farmers and strengthening food security. Click here to learn more.

Lawn Pollinator Challenge

About the Experiment

Pollinators, such as bees, birds, and butterflies, are essential components of our ecosystem. They help pollinate our food crops and support biodiversity. Pollinators also need food and water themselves to survive, and you may be surprised to learn that your lawn can provide essential nutrients for them. In this experiment, you’ll learn what types of pollinators hover around your lawn, what type of grasses/weeds they feed on, and how mowing your grass can affect pollinator activity in your lawn.

Details

Ages: 5-16 | Time: 10 Minutes a day for about a week | Difficulty: Easy

What You Will Need

• 4 yard stakes

• String

• Tape measure

• Pencil/paper

• Timer (phone or stop watch)

Safety Note: Some pollinators such as bees may sting when confronted or in their flight path. Be careful when observing all pollinators.

Let’s Do This!

• Measure out a 10 ft x 10 ft square in your lawn.

• Add yard stakes to the corners and add string around the stakes to mark the square you will be observing.

• Record when the lawn was last mowed, and measure the height of the grass. Write down all the plant species you see (grass, weeds, dandelions, etc.) If you are unsure of a grass species, take a picture and look it up on your phone.

• Set your timer to 10 minutes, and during that time observe from a safe distance insects/birds that visit your 10x10 area. Write down all insect/bird types and what they are doing (hovering around, landing on a flower, sitting on the grass, etc.)

• Wait a few days until the grass grows approximately 1/2 to 1 inch, and then observe for 10 minutes, recording what you see.

• Wait another few days until the grass grows another 1/2 to 1 inch, and observe again and record what you see.

• Wait until the lawn is freshly mowed, and then observe and notate your observations one last time.

• Make sure to remove the stakes and string when mowing, and then add them back after mowing. Remove the stakes and string at the end of the experiment.

Observations

• How many plant species did you find in your lawn? Do you think having more or less plant species is beneficial for pollinators?

• Which insects/birds frequented your 10x10 square? What did they appear to be doing? What do you think they were looking for?

• As the grass grew longer, did you see fewer or more visitors to your 10x10 square? Did you see more of a certain species (bird, bee, butterfly, etc.) as the grass grew longer?

• What happened after the lawn was mowed? Did you see more or fewer visitors to your 10x10 square?

• What does this experiment tell you about your lawn’s ability to attract pollinators? How does mowing affect pollinator activity in your lawn?

To learn more about ARS’s research on lawns and pollinators, watch this video.

Download the printable "Lawn Pollinator Challenge" project PDF:
https://www.ars.usda.gov/ARSUserFiles/oc/AgLab/projects/Pollinator-Challenge/Lawn-Pollinator-Challenge.pdf 

Keep Your Apples from Browning

About the Experiment

Apples are a tasty and nutritious treat. However, when sliced they can brown quickly, due to the breaking of the apple’s cell wall and its exposure to air. This chemical exposure produces brown pigment in the flesh of the apple. The apple slices are still safe to eat, but not very appealing looking and could have an off taste. The good news is there are several natural preservatives that can be used to prevent or delay browning when apples are sliced. But which natural preservatives are most effective, and do any affect their taste? Well, let’s find out!

Details

Ages: 5-12 | Time: 1 Hour | Difficulty: Easy

What You Will Need

• Apple slices from four apples (any apple variety will work)

• Water (control)

• 1-2 cups of lemon juice, orange juice, green tea (cold or room temperature) and a vitamin C solution

• 5 clear cups

• Measuring cups

• Paper towels

• Timer

Let’s Do This!

1. Fill each cup separately with 1-2 cups of tap water, lemon juice, orange juice, green tea, and a vitamin C solution.

2. Cut each apple into 4-6 slices (ask an adult for assistance with cutting).

3. Place 2-4 apple slices in each cup, making sure they are submerged into the liquids. Soak the slices for 2 minutes. Set aside 2-4 apple slices to see how they react to no solution.

4. Remove the apple slices from the liquids and place them on paper towels, keeping marks on which apples were in which solution. Do not dry them.

5. Observe any browning of the apple slices at 0, 10, 20, 30, and 40 minutes.

6. Mark the results down on a spreadsheet showing the solution (row) and the timeframe (column).

7. You can use a browning scale of 1-5, with 1 being no browning at all, 2 a little browning, 3 some browning, 4 significant browning, and 5 completely brown.

Observations

1. At what time increment did you first start seeing browning on any apple slices? Which solution(s) were they in?

2. Which solution(s) offered the best protection against browning? Which offered the least?

3. Did any solution(s) provide complete protection against browning after 40 minutes?

4. Sample the apples with the least amount of browning. Did any taste different? Did any taste like the liquid they were soaked in?

5. What results surprised you the most, and why?

6. What does this experiment tell you about oxidation and preservation?

7. Do you think natural soaking methods like this are effective in keeping apple slices from browning and still tasting good?

To learn more about ARS’s research on apples, click here.

Download the printable "Keep Your Apples from Browning" project PDF:
https://www.ars.usda.gov/ARSUserFiles/oc/AgLab/projects/Apples/Keep-Your-Apples-from-Browning.pdf