Here are some simple rhymes/ sayings that I use with my students to get them to sit at the carpet, line up or to get their attention.
1) Au tapis je vois?
And the students say "Jambes croisees, dos etroit, et mains comme ca"
2) When I loudly say MOUCHE MOUCHE MOUCHE (like they are little noisy flies), the students are always so excited to say "fermez les bouches", before showing me who can be the most silent
3) In line we recite the following call and response (to the tune of sound off) each time before we head out for recess https://www.youtube.com/watch?v=ZJNQZ_fot0A
Teacher: "Je suis pret et je suis cool"
Teacher: "Je suis tourne et au debout"
Teacher: "Je marche bien et ecouter"
Teacher: "Parce que j'aime bien aller jouer!"