For a few years now I've been successfully using the quadratic formula song to make it stick in the students' minds, and sure enough it works if "they work it". I have students coming back to visit and saying, "you know, I needed the quadratic formula the other day, and I still remembered it because of the song!"
So. Even though I'm teaching high school, and even though they were supposed to become proficient with fractions (+, -, x, /) in elementary (middle?) school, there are STILL students (gasp!) that can't manipulate the little buggers.
I came up with a fraction song that incorporates +, x, / to the tune of "jingle bells", and they've been practicing it for the last 2 days. It's too funny to watch them .... and the way various classes go about singing it. Some just really get into it and boisterously sing. Others, it's like they're reciting a death pledge or something .... all monotone and quiet. Too funny. Whatever, as long as they learn to do what they need to do. I'm going for 100% accuracy in 100% of my classes. Let's see what happens.