The form 1099-R is a report of a distribution from a broad spectrum of retirement plans, the Roth IRA being just one of them.
Is this 1099-R from your teacher's retirement plan? Then I would guess that it is probably not a Roth IRA, unless your retirement plan was set up as a Roth (not common).
You can tell something about the plan by
1. Looking at the box to the right of box 7, where there is a small unnumbered check box labeled "IRA/SEP/SIMPLE". if it is a Roth, it should be checked (but I bet it isn't).
2. Checking the code in box 7 which can vary based on the type of plan. If the code is 7 (for a normal distribution from a qualified retirement plan) , then this is not a Roth IRA.
Of course, you can always contact the organization that sent you the 1099-R and ask them what kind of plan it is.
If you are curious as to the meaning of the codes, please see
https://ttlc.intuit.com/replies/4194736