(upbeat music)
Welcome back to Scratch Music and Sound, day six.
Today you'll build a music video
while learning about an important
computer science concept, procedures.
In computer science,
a procedure is a set of many instructions
packaged together to create a new command.
In Scratch, the new command, or procedure,
is a new custom block which you will create.
For example, you could create a block named CS First
that instructs the computer to make the Scratch cat
run on the screen and say, CS is awesome,
and then run back off the screen.
Now we want the cat to appear in your program,
just drag out the CS First block
instead of creating a whole new set of blocks
to make the cat appear and talk.
The CS First block as an example of a procedure.
Procedures are a short way to give the computer
a set of instructions and they are another way
computer scientists like you save time when coding.
Today you use procedures to create
custom blocks to make your music video.
Scratch is a popular tool for making music videos.
You can upload a song and then animate it
using the code blocks you learned about in this club.
This is an action packed music video,
but the code isn't that complex.
The animations are simply costume changes.
Take a look at some other music
videos built with code blocks.
♪I'm blue da ba dee da ba daa ♪
♪ Da ba dee da ba daa, da ba dee da ba daa ♪
♪ Da ba dee da ba daa ♪
♪ The rooftops I remember there was snow ♪
♪ White snow ♪
♪ Clearly I remember ♪
♪ From the windows they were watching ♪
♪ While we froze down below ♪
♪ When the future's architecture ♪
♪ By a carnival of idiots on show ♪
♪ You'd better lie low ♪
(guitar riffing)
Those are some awesome videos created by
Scratch computer scientists like you.
Many of them built using blocks you had the chance to use.
Of course, creating music videos and animating them
can take a lot of time, but the end result is ridiculous
and those videos can be seen by thousands of people.
You can have a big impact on a lot
of people and your experience with
computer science will have life long value.
Take a look at this sample video that shows
some techniques that you can learn today.
Each block you see here behaves in a fun and unique way.
You'll get a chance to choose which of these behaviors
you want to create in the next screen cast.
First, start a new project.
Name it music video and delete the Scratch cat.
Next, click on the music library link
on this CS First page and listen to a few songs.
(rock and roll music)
(jazz music)
(slow guitar music)
In the new project that you just made,
click on the stage and the sound tab
and then upload the song that you chose.
Now you may need to look at your downloads folder
to see where the song is placed, but that's okay.
Now it's your turn.
Create a new project named music video
and delete the Scratch cat.
Choose a song from the CS First music library
and upload it to the stage area of your program.
After completing those steps, go back to
the CS First page and click the green arrow
to move onto the next screen cast.
