i want to make quadcopter sensing temperature with arduino....what material should i buy...and i m also new to arduino..
An arduino and a temperature shield to start.
Then an sd card shield to store the temperature data if thats what you intend to do with it.
There are several ways to measure temperature:
Measure the resistance of a thermistor and do some complicated calculations.
Measure the voltage from a thermocouple and calculate (using a MAX31855 chip).
Use an LM35 analog thermometer connected to an analog input and do simple math.
Use one or more DS18B20 OneWire temperature sensors and the OneWire library to read them.