Expression: On my mind

If something (or someone) is on your mind, it means that you're thinking about it (or him/her). For example:
You: "Do you have a minute to chat?"
Your friend: "Sure! What's on your mind?"
Your friend is asking what you're thinking about. Sometimes people say "I have a lot on my mind" which means that they have many things, and probably heavy ones, to think about right now.
There's a famous song called Georgia On My Mind.
Here are the lyrics for this song:

Georgia, Georgia,
The whole day through
Just an old sweet song
Keeps Georgia on my mind

I say Georgia Georgia
A song of you
Comes as sweet and clear
As moonlight through the pines

Other arms reach out to me
Other eyes smile tenderly
Still in peaceful dreams I see
The road leads back to you

I said Georgia,
Ooh Georgia, no peace I find
Just an old sweet song
Keeps Georgia on my mind

Other arms reach out to me
Other eyes smile tenderly
Still in peaceful dreams I see
The road leads back to you

Georgia, Georgia,
No peace, no peace I find
Just this old, sweet song
Keeps Georgia on my mind
I said just an old sweet song,
Keeps Georgia on my mind

The Georgia that Ray is singing about is in the United States, in the south. I was born there, and my parents live there. I'll be visiting them very soon, so they're on my mind! I won't be blogging again until the first week of May. Until then, I hope you have a great couple of weeks, and that you only have wonderful things on your mind!