topperlearning.com uses simple progressive HTTP .flv streams. You can copy such streams from the cache of your web-browser. You can also download such streams with many programs, including freeware Fast Video Download extension for Firefox (works in Windows, Linux, Mac OS), freeware Freecorder 4 (Windows), Jaksta Free Media Recorder (Windows), paid Replay Media Catcher (Windows).

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FAQ: How to record/download/capture/save Adobe Flash .FLV / .MP4 video HTTP stream from embedded player