I've focused on using an Arduino "Feather M0 Adalogger" (https://www.adafruit.com/product/2796). It has as a MicroSD card slot, and LiPo battery charger on-board. Neither battery nor memory card are included in the Feather purchase. The battery is only needed if you want to use your project without a USB power cable. The SD card is only used if you want your sketch to read or write (or both) data to the card (this makes it easy to exchange data between your Adalogger and another computer), so you can then analyze and visualize the data. I also suggest that you get pins or sockets for your Arduino, so that you can use it with breadboards and wires.

We want you to get started smoothly, with some early successes. I picked an Arduino without WiFi or Bluetooth for a few reasons;

• Students can get access to "Cloud Services" cheaply (and some for free), but it can cost money to store your data, and when you graduate, you lose the free access.
• The Internet of Things (IoT) is still evolving. Even if we teach you how to do it, you'll need to learn the new way(s) in another year or two. If you get really interested in this, you'll need to spend more time to keep up.
• Data Security isn't "baked in" to most embedded controllers. Any data you put "in the cloud" may be vulnerable. That means that hardware and tools and libraries will need to change in the next few years. 

There will be a "class kit", consisting of two I2C multiple-function sensors (35 pcs each), so that the students can work on a set of sketches and projects. We picked environmental sensors, so you can do tests in parallel, and compare results. They are a UV/IR/Visible light sensors https://www.adafruit.com/product/1777  and  Temperature and Barometric Pressure https://www.adafruit.com/product/992  .

    There will be a variety of other sensors to experiment with, in smaller quantities. These will allow some students to try other sensors, but not at the same time. Some are more useful for short-time (minutes or hours) experiments, and others may be more useful in longer-term projects (many day data collection). Some students may want to pursue looking at data, turning it into graphs, comparing data from many tests, and looking for trends.  These are the other sensors (and quantity), and they will likely need to be checked out like a library book, and returned in working order. 

•       Basic Real-Time Clock (15):   https://www.adafruit.com/product/3295
•       RGB Color Sensor (15):  https://www.adafruit.com/product/992  
•       Visible Light Sensor (5):  https://www.adafruit.com/product/2748  
•       UV Index Sensor (5):   https://www.adafruit.com/product/2899
•       Basic Humidity (5):  https://www.adafruit.com/product/386  
•       Humidity & Temp (15):   https://www.adafruit.com/product/3251
•       Waterproof Temp Probe (10):  https://www.adafruit.com/product/381  
•       Analog Temp Sensor (10):  https://www.adafruit.com/product/165
•       Air Quality Sensor (5):  https://www.adafruit.com/product/3566
•       8-GB SD/MicroSD memory card (15):   https://www.adafruit.com/product/1294
•       LiPo Battery, 3.7v, 500 mAh (10):  https://www.adafruit.com/product/1578
•       Neopixel display strip (10):  https://www.adafruit.com/product/1426

  ( * If you get header pins, to use these with breadboards, you'll need to solder about 80 pins for the list above.)

Beside the parts listed above, consider if you have enough of these other things;

• A few good soldering irons! You will need to solder in many pins! (There are 80 pins for one each of the list above. But the list above in the class quantities means soldering more than 2000 pins!)
• Enough USB power + data cables for all of the Arduino boards.
• Small or Large breadboards (at least one for each student).
• Small storage tubs, for students to keep their kit together, so they can quickly take their project out and work on it.
• Many, MANY short jumper wires! Many red and black and other colored male-to-male jumpers, so you can connect all the sensors to the Arduino on the breadboards. 

  As you go through the class, I strongly encourage you to do the initial projects first, because the projects are intended to teach you things besides how to plug the wires in to make the project work. Copying and pasting is easy to make something work, if the wires are in the right place. But I'm working on project tasks to lead you to think, to make observations and to form conclusions (and then test your conclusions). To this end, I won't be posting all of the projects first. I'll keep posting more projects to the Assignments page as the class progresses.

  Some of you will learn to solder connections, which can be a useful skill to help resurrect a dead device. I also hope you will start to collaborate with other students, sharing your questions and discussing your results (and data) and discoveries. Collaboration is an important skill that will help you be successful in many aspects of your life.

  As you progress through High School, you'll be in other classes which will want you to test ideas, collect data, report on results. I'm hoping that this class will show you have an Arduino (or other embedded controller) can be a simple tool to help you do some other tasks.