We use JSON as a method of communicating the environmental settings (via a “Recipe”) to the MARSfarm Version 1. If you are unfamiliar with JSON, but are interested in learning about it and potentially teaching your students some coding concepts - I strongly encourage you to check out this conversation I had with ChatGPT about how to teach students about JSON using the MV1_Tomatosphere recipe. JSON stands for JavaScript Object Notation. It’s a lightweight data-interchange format that’s easy for humans to read and write and easy for machines to parse and generate. JSON is often used to transmit data between a server and a web application or between different parts of an application. It’s like a universal language that both people and computers understand, helping them communicate more efficiently.
The conversation below is from when I used ChatGPT to help me explain JSON to a 7th grader using the MV1_Tomatosphere recipe as an example. To see the complete recipe for yourself, check out this forum post: Tomatosphere Recipe - Using your MV1 to grow tomatoes!.
Peter’s prompt to ChatGPT: Explain JSON to a 7th grader with no understanding of code or programming logic. the context is that they’re school so assume they want to learn but use analogies and make it interesting.
ChatGPT-4: Let’s imagine JSON as a magical backpack that you take to school. This isn’t just any backpack; it’s super organized and helps you find exactly what you need, when you need it. 
…
The Magical Backpack (JSON Object)
When you open the backpack, you see different pockets and compartments. Each pocket has a label, like “Pencils,” “Notebooks,” or “Snacks.”
Labels and Stuff Inside (Key-Value Pairs)
The label on the pocket is like the “key” in JSON, and the stuff inside the pocket is the “value.” So, if the label says “Pencils,” you’ll find pencils inside that pocket.
Multiple Items (Arrays)
Some pockets might have more than one type of item. Imagine a pocket labeled “Snacks,” and inside, you find an apple, a bag of chips, and a juice box, all neatly arranged in a specific order. That’s like an array in JSON!
Nested Pockets (Nested Objects)
Now, let’s say you have a pocket labeled “Math Supplies,” and inside that pocket, you find a smaller pouch that holds a calculator, ruler, and protractor. That’s a nested object!
The Magical Backpack in Action (JSON Example)
So, if your magical backpack were written in JSON, it might look something like this:
{
"Pencils": 3,
"Notebooks": 2,
"Snacks": ["Apple", "Chips", "Juice Box"],
"Math Supplies": {
"Calculator": 1,
"Ruler": 1,
"Protractor": 1
}
}
Isn’t that cool? Just like you can quickly find what you need in your magical backpack, computers use JSON to quickly find and organize information. 
So, the next time you pack your backpack for school, think about how it’s like creating your own JSON object, making your life easier and more organized!
Peter: great! now use the same analogy to explain how this JSON file works. My goal is that they could then try to “read” this file to tell me what some of the settings are. For context, this JSON will be used to provide settings for the lights, temperature, irrigation, and airflow in a countertop-sized smart greenhouse…[copied text from MV1_Tomatosphere recipe]
ChatGPT-4: Absolutely, let’s dive into this magical greenhouse backpack! 
…
The Magical Greenhouse Backpack (JSON Object)
Imagine this JSON file is like a super-detailed magical backpack for your smart greenhouse. This backpack has pockets for lights, temperature, irrigation, and airflow. Each pocket has specific settings to make sure your plants grow perfectly!
Labels and Stuff Inside (Key-Value Pairs)
_id: Think of this as the backpack’s unique ID tag.model_name: This is the type of backpack; it’s a “TemplateRecipe.”recipe_name: This is the name of the plant-growing plan, called “MV1_Tomatosphere.”
Multiple Items (Arrays)
phases: This is like a big pocket that has different sections for each growing phase of the plant. Right now, it has a “vegetative” phase.
Nested Pockets (Nested Objects)
Inside the “vegetative” phase, you have smaller pockets for:
circulation_fan: This pocket tells the fan to start at 0 hours and 1 minute with setting 1.temperature: This pocket sets the temperature to 60°F at 0 hours and 1 minute, changes it to 75°F at 6 hours and 5 minutes, and back to 60°F at 20 hours and 5 minutes.pump_amount: This pocket tells the irrigation system to pump 80ml of water at different times starting at 9 hours and 5 minutes.light_intensity: This pocket sets the light intensity. For example, at 9 hours and 5 minutes, all the light colors (white, blue, green, red) are at their maximum (255).
Reading the Magical Greenhouse Backpack
So, if you were to “read” this backpack, you’d know that:
- The fan starts at 0 hours and 1 minute with a setting of 1.
- The temperature is 60°F but changes to 75°F at 6 hours and 5 minutes and back to 60°F at 20 hours and 5 minutes.
- The irrigation system pumps 80ml of water four times, starting at 9 hours and 5 minutes.
- The lights are off but turn on to full intensity at 9 hours and 5 minutes and turn off again at 23 hours and 5 minutes.
Isn’t it cool how organized this magical greenhouse backpack is? Just like this backpack helps your plants grow, the JSON file helps your smart greenhouse know exactly what to do!
