This is a “two-fer” – one online link and one link to a paper activity.
The Real English Web site offers a video of real people, both British and American, telling the time. There is a listening and speaking exercise that follows with only American English. The second exercise is a dictation of the video script which gives students lots of practice spelling out numbers.
Real English always has a video without subtitles and one with subtitles. Remind your students to listen to the video without subtitles first, and many times. The main goal is to improve listening comprehension, and they need to listen more than once to get their ears attuned to native speakers. Watching the closed-captioned video is good preparation for the dictation exercise.
For very low-level students, here is a paper-based matching activity of times and clocks.