Moving Sprites in Scratch Exploring Computer Science – Lesson 4-4

Journal Entry ●Briefly describe how you graph something in your Algebra class. ●Draw me an example graph with 5 points. ●Tell me the points that you graphed

What do you think… ●Download the file moving.sb from Google Drive. ●Open moving.sb in scratch. ●Click on the “Click here for the Homework” link on the web site. ●Complete the homework. A word version of the questions is also on the website. You might want to have that open. ●Make sure you submit when done!

The Stage ●The “stage” in Scratch is simply a Cartesian coordinate system with point (0,0) in the middle:

Moving Blocks ●The “move” block moves the sprite forward that many units. ●The direction depends on which way the sprite is facing.

Moving Blocks ●The “go to” block instantly moves the sprite to that coordinate on the stage. ●The direction the sprite is facing will not change

Moving Blocks ●The “glide” block moves the sprite to that coordinate on the stage but unlike the “go to” block the sprite will move across the screen to that location. ●The direction the sprite is facing will not change.

Repeat Blocks ●The “repeat block” will do a section of code a set number of times. ●This is called iteration or looping ●Iteration is a programming concept common to all programming languages.

Start Blocks ●The code in a “when green flag clicked” block is executed when the user clicks on the green flag to run the program. ●Use this to move sprites to their original position.

Rest of Today and First Part of Monday ●Use what you’ve learned about moving to get the cat to run the bases (as realistically as possible – bases are run counter clockwise. ●Make sure that when you click the green flag, the cat starts at home plate again. ●Extra Credit: Make the cat change costumes so that it looks like it is running as it circles the bases.