ALGORITHMS and PROGRAMMING - K-2

     While the CS standards require that K-2 students understand and use loops, sequences, and events, they state that these concepts can be learned either through the use of a computer and a block-based programming language or while unplugged.

Unplugged

     A quick search of Pinterest will result in a large number of unplugged, pre-coding activities.  Many of them make use of cards with images showing different "commands" such as move forward, turn left, or stop.  Students may be given a gridded board with obstacles, and they must choose the correct sequence of commands to guide a character through a maze.  One example from Pinterest shows such a game: children have to guide a gingerbread man past a number of obstacles to reach a river. https://www.youclevermonkey.com/2017/02/early-years-STEM.html

     There are also a number of devices such as the Coderpilar, Programmable Mouse, and Botley, that allow students to enter a sequence of commands (usually directions) by linking pieces or pushing buttons.  These are relatively inexpensive (all are available through Amazon.com) and very easy to use.  Botley, the left image, has students enter a sequence of commands using the remote then send the program to the robot.  The Coderpilar (right) has students link a sequence of command sections together to form the caterpillar's body.  Pushing a Start button has the robots execute the program.

Computer/Tablet

     If  you have access to Tablets (IPads or Android) or Chromebooks, I think the best option for teaching and learning coding would be Scratch Jr.  It is a free download and there are lots of tutorials, blogs, books, and other resources available.  A great resource is the www.scratchjr.org site.  The Teach tab has sections for for Activities, Curricula, and Assessments.
     Scratch Jr is a simplified version of Scratch.  It's block-based programming with a limited number of blocks.  It works much the same way as Scratch - you are adding characters (Sprites) to a background, then programming each Sprite.  You build the program by connecting different color-coded blocks (blue for motion for example.)  Each Sprite has it's own program.  It's very easy to add interaction, movement, speech (recorded or text balloons), and you can change backgrounds.
     A great free resource is the list of blocks and functions provided as both large printable pages (for unplugged use or pre-coding planning) here, or in list form here.
     Scratch Jr is a great way to learn the basics of coding and while it's recommended for K-2, I think it would work well for pre-K and higher grades, for students who may have not had any previous programming experience.  It's great for adults as well.
   

     This is a screen shot from a Scratch Jr program.  On the left, you see the four sprites used in this program (cat, butterfly, pink flower, and yellow flower.)  The plus sign under the last sprite allows you to add more sprites - you can choose from a library, upload an image, or design your own sprites.  On the right are the backgrounds.  Again, you can choose from a library, upload an image, or design your own background.  

     Under the sprites and backgrounds, you see the command options.  Clicking on a color coded block shows the various commands available for that option.  You then drag the command you want for the program down into the programming area below. In this example, the orange block has been clicked so you can see the four options (setting time, halting, setting speed, and using a loop.)  Below that bar, you see the programming area.  In this case, the cat sprite has been clicked, so this program is for the cat.  You see two yellow events, one a green flag, the other an icon showing a figure being pressed.  The first event is for the green flag (it's in the upper right corner of the screen).  When the flag is clicked, the program connected to the flag block begins.  

     For this program, three blue motion blocks have been placed inside an orange block.  This is a loop.  That means the sequence of motions - jumping up and down twice, moving four steps ahead, moving four steps back - will be repeated 4 times.  The advantage to creating a loop is that you don't have to do the same sequence of motions 4 times, dragging down 12 blue blocks.  The second part of the program just has two blocks - a yellow event block that starts that program when the cat is clicked and a red block that tells the program to switch to the next background. Each sprite has its own program.  So, when you click the butterfly, you'll see its program.  

     You can see some good examples of Scratch Jr projects (and a good discussion of the benefits of using ScratchJr) here: https://www.coderkids.com/blog/scratchjr-projects-for-kids  At the bottom of the page for this site the author has provided a list of good Scratch Jr resources.