The block palette is an area of the graphical user interface located between the stage, sprite pane and scripting area. The blocks are located to the right of the categories, which can be clicked to automatically scroll to that category. The whole list can be scrolled through.
Using the Palette
By selecting the “Code” tab in the upper area of the Scratch program, the block palette will be opened. The block palette consists of every block that is built into Scratch. Some of the blocks take on certain values by default in their parameters, but others are variably controlled depending on the context of the associated sprite’s current values. For instance, clicking and manually moving a sprite will adjust the x and y coordinate values within various motion blocks to its current position.
In the block palette, built-in reporter variables such as direction and x position have a checkbox present adjacently to the left of them in the palette. By clicking on this checkbox, it displays that variable on the stage, not in block form, but in the form of its output value. By unchecking the box, it will hide that variable from the stage. Even when a different sprite is selected from the sprite pane or the stage, the variable display will remain present on the stage if it was previously checked.
Blocks can be clicked and dragged into the scripting area via any pixels on the block aside from drop-down arrows. One must click the mouse on a block and hold that click until the mouse pointer has reached the scripting area, after which it can be released to place a block in the code area. One does not need the entire block to be contained within the area, as the code area will adjust its dimensions to accommodate the block. If a block was grabbed by mistake, simply drop it back into the block palette to remove it.
Right-clicking on a block in the palette does not open up anything, contrary to the many options that show up by right-clicking a block in the code area.