Education, bullying, adventure, dreams, nano technology are some common topics to deliver in the morning assembly.

Hope this helps:)
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These may help you.........
1.importance of the particular day
   on which you are going to deliver the speech.
2.importance of education.
3.some undeveloped areas in your surrounding.
4.planting trees.
and some attractive topics.
pls mark as best if helpful.
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