This has such a small, country town feel to it, when I understand since I've lived in one for the past 15 years. Great idea to do an acrostic, I haven't done many of them and they can be tricky, so I enjoyed reading this. A few suggestions:

"Trains to fill even when i'm ill"

- Felt like the rhyme is forced and doesn't add enough meaning, here and in the rest of the poem. There was not a rhyme scheme that was consistent, so maybe don't worry about rhyming? Simply my opinion though. I didn't think you being ill was that relevant to open with. Give more description, the sound, type of train even, etc.

"Own the land and cover up the sand
Wake up every day wanting to play
Never too little and never too much"

- These were short lines but I felt your sense of adventure here. The sand, (made me think of sandboxes), and the awe of being young and feeling free, one with nature.

"Start of small then the barn gets full
Helping all my friends is my trend"

- "of" should be "off". Tie in more of a connection with this barn. I felt like you introduced it too suddenly. Who's barn is it? I also thought the "trend" part was unnecessary and the rhyme forced.

"I hope to build the "city" one day
Practise and patience then you just may"

- I really liked these last two lines honestly as your ending. It gave me that hope again, imaging what grand "city" this could be, the dreams you want to come true. There's a bit of mystery in the end as you are a bit vague, yet it makes me think of growing up and learning how to build one's own path, one's own "city".

Keep writing!

I gave you a 4/5 it was good, and you have potential,
but try to add more rhymes, it was a little bumpy when i was reading it.. so try to be smoother next time, keep me updated!