Resolved: NATO should strengthen its relationship with Ukraine in order to deter further Russian aggression.
In your initial research phase for Nationals, do not discount getting to know NATO. Great teams will not only explain the relationship between NATO and Ukraine and advocate their position. Great teams will know NATO as if it was their old friend. At some level this topic gets back to the theory of why NATO exists and if it is effective in its mission. For that reason, get to know NATO! Here are some resources to get your started.
A pdf published by NATO itself, this gives a great background overview to all that is NATO. As it is published by NATO, however, it won’t give you anything against the organization.
Another NATO publication, but great starting place.
A CSPAN Video where panelists talk about NATO and Europe.
Published by the International Socialist Review, this gives a great history of NATO as well as arguments against its existence.
Free backfiles downloaded from Speech Geek Market from October 2010 PF Topic: Resolved: NATO presence improves the lives of Afghan citizens. Backfiles, whether from PF or from Policy, can be helpful on making arguments general to any NATO topic. These backfiles can be great evidence to have and good places to develop your working knowledge of NATO.
Wikipedia is also always a great place to start if you take the time to go through the citations – that is where the evidence gold lies.
Good luck getting to know NATO!