Datasheet

} else if (photocellReading < 500) {

Serial.println(" - Light");

} else if (photocellReading < 800) {

Serial.println(" - Bright");

} else {

Serial.println(" - Very bright");

}

tempReading = analogRead(tempPin);

Serial.print("Temp reading = ");

Serial.print(tempReading); // the raw analog reading

// converting that reading to voltage, which is based off the reference voltage

float voltage = tempReading * aref_voltage / 1024;

// print out the voltage

Serial.print(" - ");

Serial.print(voltage); Serial.println(" volts");

// now print out the temperature

float temperatureC = (voltage - 0.5) * 100 ; //converting from 10 mv per degree wit 500 mV offset

//to degrees ((volatge - 500mV) times 100)

Serial.print(temperatureC); Serial.println(" degrees C");

// now convert to Fahrenheight

float temperatureF = (temperatureC * 9 / 5) + 32;

Serial.print(temperatureF); Serial.println(" degrees F");

delay(1000);

}

OK upload this sketch and check the Serial monitor again