Sound Bible is one of my two go-to resources for free audio files. The other is Dig CC Mixter. My students use both of these resources to find music and sound effects to use in their projects.Sound Bible is a good place for students to find all kinds of free sound effects recordings. Students can download files as MP3 or WAV files. And best of all, students don't need to register on the site in order to download the files. But they do need to remember to cite the source of the sound effects as most are labeled with a Creative Commons license. Learn more about Sound Bible in my short video embedded below.
Dig CC Mixter offers thousands of songs that are Creative Commons licensed. The site is divided into three main categories. Those categories are Instrumental Music for Film & Video, Free Music for Commercial Projects, and Music for Video Games. Within each category you can search according to genre, instrument, and style. Here's a little video overview of Dig CC Mixter.