I feel like I've shared this resource before but I couldn't find it so maybe it will stick this time :)
This is a good resource created by "Dr. Andryj Borys, a main-group chemist, phosphorus fanatic and Schlenk line enthusiast." He is currently a postdoc in Canada, headed back to Europe in 2020 (supposedly..)
this resource describes the use of a Schlenk line in quite a bit of detail, with a variety of standard applications (cannula transfer, sealing NMR tubes).
A student can use this resource to learn general features of a Schlenk line.