Over 3 years ago, Amy wrote about how easy it is to record audio via the vocaroo website on any web browser on a computer. It still is very easy! Check out that post if you want to learn more.
Another great audio recording option is Voice Record Pro on the iPad. Not only does it record easily, but once you hit "stop," it gives you the option to upload to Google Drive! Students can use this to record any kind of audio, for something different in your classroom. Have them make a podcast teaching something they've learned to a younger grade, or interviewing each other, or reading a story they wrote, or performing a dramatic reading!
For middle school or high school using Chromebooks or Dell laptops, Beautiful Audio Editor is a great option for students to record and edit audio. Once exported, students can easily upload to Google Drive or post to their blog.