Things which i present them :
1.A PLANT: as they have nt seen it in their whole life. and probably they'll work on it 2 produce it.
2. A PEN AND PAPER: to give him a autograph as a memory
3. ANY POEM: as literary work remains for ages
4. ANY SONG: as he can listen our language
5. AN INSTRUMENT: so that he may get some idea to use things.
6. MATCH BOX: 2 show him light(as it will nt burn loss of atmosphere)
7. WATER: to tell him that v r dependent on this

I would take 

1)a few jewels to show them  a few of our beautiful and important  items
2)few photos of the diversity to show uniqueness of our nations
3)i will take a few toys for their little ones to play with
4) i would take a few books, one for each age group, to show them our literature.
5)i would give them a facts and research book on earth which will probably help them in their research
6)give them some currency of different countries tho show trade and economy
7)a real good music collection 
8)some of our food like candy which will not rot easily (duh)
9)few different plant seeds and detailed instructions to plant them.
10)a book on our mythology.
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