When we first looked at jumping, we had to use some math to keep track of where started from in order to land in the same position. In a platform game, we don’t necessarily care where we started, we just care that we’re on solid ground.

when green flag clicked
set [y speed v] to [0]
forever
	change y by (y speed)
end

We can create a game loop that starts us out on the ground and forever applies our current speed. As the player plays the game, we’ll adjust this variable.

when green flag clicked
set (y speed) to [0]
forever
	if <touching color (#000)?> then
		set [y speed v] to [0]
		if <key [space v] pressed?> then
			set [y speed v] to (10)
		end
	end
	change y by (y speed)
	change [y speed v] by (-0.5)
end

We now have a pretty slick jumping motion.