The methodologies for supplementing classroom-based teaching and learning through technology is extensive and can include such activities as collaborative interchanges (think wikis, group projects using Google Docs, etcetera); online discourse (discussions, live chats, etcetera); the many forms of inquiry based learning such as webquests; simulations; e-portfolios; assessment and remediation systems; etcetera.... Usage of most systems can be tracked by the instructor in terms of actual time spent and frequency of use. Additionally, students can also be asked via a survey about their usage. While one cannot the students' learning, you can assess their performance. You can then consider whether frequency of participation in technology based learning opportunities correlated to more positive performance. Another option is to have a control group that is not exposed to the technological resources and compare performance across groups. I hope this helps.
The social media tools are what I would call auxiliary teaching support resources to help you to become creative in how to present your lessons to your audience/students and capture their attention. You can choose to remain as a tradition stand and deliver or chalk and talk teaching methods. However, the 21st century students will tell you straight in the face that you are a boring lecturer. Remember the old adage? No man is an Island'? You will not make an effective lecturer if you maintain your traditional classroom practices because the students are miles ahead with the Nano tech development and introduction.