Form 1040 Schedule 3-line 50 but my form stops at line 31.
No it doesn't.You're looking at the wrong form. SCH 3 doesn't even have a line 31 on it at all. In fact, SCH 3 starts with line 48 and ends with line 55. Line 50 of the SCH 3 is labeled "Education Credits from form 8863, Line 19". Make sure you're looking at the right thing. You can see what SCH 3 looks like at https://www.irs.gov/pub/irs-pdf/f1040s3.pdf
