This is an Example of how you can use the Arduino to monitor various environmental parameters And display them on a LCD screen.
Note: I Added a Real Time Clock!! To see the steps, added parts and Sketch I added new steps..
Step 1: Parts List
Arduino uno R3 or compatible 30.00
Sainsmart "1.8" TFT Color LCD Display 18.50
DHT11 Digital Temperature and Humidity Sensor 6.44
Mini Breadboard 5.00