The Battle – Easter Sunday – Jesus V. Satan

This Sunday with my 5th and 6th graders I’d like to teach them about the battle that happened during the 3 days while Jesus was dead. I need to do some research, but I’d like to explore why Jesus was dead for 3 days. I know it was prophesied in the old testament and Jesus mentioned the destruction of the temple and it’s rebuilding in 3 days… but why 3 days? The number of perfection? Is there a tie there to the Trinity? What are your thoughts?