This page contains a list of the common reoccurring things that are in Rosen YouTube Poops. A lot of these gags have even inspired YouTube Pooper's naming of channels.
Plums, (also known as Bag of Plums) which originates from the video The Michael Rosen Rap is one of the most common and reoccurring gags in Rosen YouTube Poop history. It's usually Michael's favorite food in these YouTube Poops, it's also a commonly said in some form and has also inspired quite a few YouTube Pooper's names (I.E. ThePlamzJoker, CaptainPlums, ECT).
Fantastic is usually used in videos for Michael talking sarcastically.