Education

Our 529 withdrawals were less than our qualified expenses, so definitely no tax owed.  But I don't understand how the government knows this if we don't enter all this information.  We were always told to keep every single receipt, record, etc. of what we paid for college so we don't get hit with any unqualified expenses and now it sounds like we don't even need to report that info to anyone?  Seems strange to me.  We don't qualify for the education credit or any type of credit since our income is too high, so I guess we just won't enter any info.  Thanks!