Greater Boston Trout Unlimited volunteers will teach a free Introduction to Fly Tying workshop on Saturday, Jan. 24, from 9:30-11:30 a.m. at the Hopkinton Public Library. The class is beginner-friendly and open to anyone interested in learning the basics of fly tying. All equipment and materials will be provided by Greater Boston Trout Unlimited. For more information and to register, visit tu.myeventscenter.com/event/Introduction-To-Fly-Tying-Workshop-119952.