Good luck starting this puzzle.  

You'll stop where you always do.  

My middle is in the ending.  

You can see on the outside that I skipped school,  

but beneath that you'll find I'm deeper.

What am I?

Hints 1:

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>  Your best shot is to start with my beginning and ending. Some users here have already identified those. "My middle is in the ending" probably won't make sense until you find my ending. If you strip away the parts of me that refer to skipping school, you'll find something that could mean the same thing as "deeper."
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