This is a really wonderful tool to create short audio recordings and share them with your students on your classroom blog/site/wiki. The process is very easy and all it takes is a sign-up and the service is free of charge. One good thing about soundCloud and which you can use with your students is that this tool allows you to add comments to any given moments in the podcast. This could be used by students to give feedback and share comments with each other.
Vocaroo is another awesome web tool to record and share audio clips. Vocaroo does not require any sing-up or software download, just head over to its homepage, and click on record and after you finish you will be provided with links to share your recording with others. Vocaroo also generates a QR code for your podcast.
3- VoiceThreadVoiceThread makes it easy for users to add voice annotation to an artifact, which might be a document, a slide presentation, a video, or a collection of photos. Commentators can add remarks by means of microphone, webcam, keyboard, or telephone. The resulting Flash-based animation contains the original artifact and the commentary on it. In educational settings, students can post visual media, instructors can comment, and peers can offer verbal or text-based assessments. What sets VoiceThread apart from other post-for-comments sites is the ease with which voice commentary can be added
4- AudioBooAudioboo is an application for recording and sharing your voice with the world. This free version allows you to create audio up to 3 minutes in length and post that to your own account on the web. You can add titles, tags, geolocation info and a photo to the recording before you upload it and we'll save all that with the file. The audio can then be shared with your site visitors or via Facebook, Twitter & other social networks by managing your account at http://audioboo.fm.
If you are looking for educational podcasts to help you in your professional growth , this list could of great help.