Project2 - Led green does not light

I offered the The Arduino Starter Kit and Basic Kit at my 13 years old son for his birthday

I tryed to help him but i am as a beginner as he is ...

We pass the Project 1 - Yes :slight_smile:

But we don't understand why the project 2 doesn't work
the green LED doesn't light
and when whe swith the button on, the red LEDs flashes well

something "strange" also : when we cancel the ground wire between the white pin board and the arduino board the green LED light and the RED LEDs flashes ...

So we are really beginners ... and we don't understand the trouble ...

Could you help us ??

make sure that switch is turned right and when switch is not pressed the green led should be on and reds off and when pressed the red ones should flash back and forth. Try using another LED for green and make sure you understand and have cathode to resistor to ground and anode to pin 2 of Arduino. The LED cathode an anode are important to be in the right way. Also those crummy little switches they use must be turned the right way. Remove the switch take a wire from +5 and touch pin 2 side of the 10 K resistor (green wire my diag) and green should go off and reds flash you can msg me for more help. Also triple check your code especially brackets and semi colons. I am not sure which ground you removed. OK I think the green LED may be in backwards..Don't run without the black ground at any time or it could damage Arduino.