Scratch Programming: Chapter Notes | Computer Application: Class 10 PDF Download

➢ Scratch is a simple environment designed by the Kindergarden Lifelong Learning Group at MIT to introduce some basic programming concepts in a fun and interactive manner.➢ Elements of Scratch
➢ There are four main elements of Scratch: the stage, the sprites, the script and the programming palette. These elements can be compared to a play.
Four main elements of Scratch:
(i) Stage: The Stage is where you see your stories, games, and animations come to life. (ii) Sprites: are the actors or main characters of the project. Sprites are programmed to do something in Scratch.
(iii) Script: tells the actors what to say or do. Each sprite is programmed with a script.
(iv) Programming palette: elements used to program the sprite to do or say something. Sprites must be programmed to carry out every function you want them to perform.➢ Blocks in Scratch

(a) Motion blocks are used to set the position of sprites on the stage or their movement, to turn and rotate the sprites and to make the sprites bounce when sprite touches the boundary of stage. They are medium blue in colour. You can only use motion blocks with sprites, not with the stage.
(b) Looks blocks are purple in colour, and they control what your sprites and backdrop look like, the size of sprites, and whether they are displayed in front of or behind other assets. Looks blocks also include blocks that let you display text and to show or hide a sprite.
(c) Sound Blocks: The pink Sound blocks add sound to your project along with the volume settings.
(d) The green Pen blocks can be used to create interactive games where the user can draw on the stage.
(e) The brown Events blocks are fundamental to Scratch as without them, nothing will happen. Each script will have an event at its start which tells the script to run. This might be the green flag being clicked to start the project, or it might be an event that is triggered while your project is running. Use all of the events blocks with the stage or your sprites: the name of some of them will change slightly depending on which you're working with.
(f) Control blocks let you control the blocks within your scripts, inserting conditional statements, loops, repeats and pauses. They can make your code much more efficient, and can be very powerful when combined with variables and/or operators.
(g) Sensing blocks are colored light blue. They let you identify whats happening at a given point and make your sprites or background respond.
(h) Operator blocks let you make comparisons between or perform arithmetic functions on different values and can be used in conjunction with data blocks or sensing blocks among others.
(i) Data blocks let you create and manipulate data in your animations and games. You can create two types of data: variables and lists. These can be used with sprites and with the stage. Variables let you define values for a variable and then use it in your project. They are great for timing games or keeping score, or for defining how many times a loop needs to run. Data blocks come in orange for variables and an orange brown for lists.
(j) More blocks: The dark purple 'more' blocks are used to create our own blocks. These are useful for making your code more efficient.