Scratch

In broad terms, you want to create a ballon sprite that positions itself at the bottom of the screen, then starts to move up until it is popped or it reaches the top of the screen.  Once it is popped or it reaches the top of the screen, have it hide itself, maybe pause for a little while, then go back to the bottom of the screen and do it again.

Get that sprite working really well - then copy it a bunch of times, maybe change the colors of a few costumes and you are good to go 

Probably somebody not clicking away on an iPad can give you an actual script, if you want one.

aryabtsev wrote:

forever
go to x: (pick random (-240) to (240)) y: (-180)
repeat until <<<touching [mouse-pointer v]?> and <mouse down?>> or <(y position) > (170)>>
change y by (speed) //Desired speed of going up
change x by (pick random (-3) to (3))
turn right (pick random (-5) to (5)) degrees
wait (0.5) secs
end

This should work.

It is important to note that you can hold down the mouse button and simply drag it to pop the balloons.  If you want a script that requires clicking the balloons, you'll need to use variables (just ask if you want it)