If you have D.EL.ED qualification and 50% in your 12th then you would only be eligible for appearing Lower Primary examination. And if you have D.EL Ed as well as graduation(no marks has been specified i.e there is no regulation that you have to have 50% in your B.A/B.sc/B.Com),you will able to appear in Upper primary examination where you will able to teach from class 5-8.