Why do so many girls in my class look at me?

I sit in the back. In one of my classes, I have literally 4 or 5 girls that constantly turn back and look at me, sometimes repeatedly glancing real quick or just staring until I catch their eye and they look away. One of them has been doing this for the past month, the others have started recently, (past couple weeks or so).

What's the reason for this? Did I do something embarrasing that I was unaware of and they keep looking at me because they think I'm weird? Do they think I'm attractive?

Thanks for your time.
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Why do so many girls in my class look at me?
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