Creative Samples Library email campaign samples:
Free Trial signup offer subject line = Is your technology investment boosting student performance?

Note: This sample is from the MarketingSherpa article:
Case Study: Trial vs White Paper Offer - Results + 5 Steps to Email Campaign Success

Sample 1 of 6 --Click here to return to main samples page for this campaign.
Note: This is a screenshot; links will not work.

MarketingSherpa Creative Sample