DoubleJump

local UserInputService = game:GetService("UserInputService")
local lastjumptick = tick()
local Jumped = 1
local function onInputBegan(input,gameProcessed)
    if input.UserInputType == Enum.UserInputType.Keyboard then
        local keyPressed = input.KeyCode
        if keyPressed == Enum.KeyCode.Space then
            if Jumped == 1 then
                Jumped = 2
            else
                if Jumped == 2 and tick() - lastjumptick <= .5 then
                    local JumpBrick = Instance.new("Part",workspace)
                    JumpBrick.CFrame = game.Players.LocalPlayer.Character.HumanoidRootPart.CFrame * CFrame.new(0,-2,0)
                    JumpBrick.Size = Vector3.new(2,.2,2)
                    JumpBrick.Anchored = true
                    JumpBrick.Transparency = 1
                    game.Players.LocalPlayer.Character.Humanoid.JumpPower = 60
                    game.Debris:AddItem(JumpBrick,.5)
                    wait(.5)
                    game.Players.LocalPlayer.Character.Humanoid.JumpPower = 50
                end
                Jumped = 1
            end
            lastjumptick = tick()
        end
    end
end

UserInputService.InputBegan:connect(onInputBegan)