I may be wrong, but it looks like hairy bittercress...it's poppped up everywhere in my lawn also here in Central Ohio. The local newspaper did a story on it last week. Very hard to eradicate, but should die off by June. It's gone wild this year.

Thanks for the quick response. I don't think that's it. The leaves of the hairy bittercress seem to be smooth while mine are jagged.

{{gwi:85226}}

This looks like it's probably Creeping Charlie. We have a great Bug & Weed Identifier app that can help you figure out what weeds are around your house. You can use it to compare weeds you find to the ones the app has on file. And if you can't make a match, you can use the app to take a photo of the weed and send it to our experts to help in the identification of the weed. The app is entirely free. You can download it here for the iPhone:
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here for Android:
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kIl0

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Spectracide Expert

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Looks to me like a variety of speedwell. Look for heart-shaped seed capsules; those are characteristic of speedwell.

I don't know what it is, but it doesn't look like Creeping Charlie to me.

After some googling, I'm pretty sure it is speedwell.