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# LED Switching
## What will we do
In this lesson we will learn how to switch two LED’s on and off one at a time. It will work in the following sequence
* Turn Red LED ON
* Wait for 1 second
* Turn Red LED OFF and Yellow LED ON
* Wait for 1 second
Run the above code for 8 times.
## Parts List
You will need the following parts:
* **1x** arduino uno
* **1x** arduino USB Cable
* **1x** Breadboard
* **3x** Jumper Wire
* **2x** LED (RED and Yellow)
* **2x** Resistor
## **Wiring it up**
Ensure that the LED are the right way around, with the longer positive leads (anodes) to the left.
## mBlock IDE
Launch the mBlock IDE () and select the Arduino Uno Device and install the [Kids Code Extension](/blocking-coding-lessons/beginner-lessons/blinking-an-led.md#install-the-kidscode-extension) \*\*\*\*
## Block Coding
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