For primary students who cannot read standard notation yet, I make a flip chart with Boomwhacker® songs on it. I only use colored dots or markers (if I can't find dots of the right color) and write the rhythm on the dot. If more than one color plays on the beats, I make "snowmen" and draw one quarter note stem for all three. I draw a dark line between the lines of music so they don't get confused. Sometimes, I even make boxes for each beat. This makes it possible for me to point and keep the students together for a concert so they don't have to memorize music. I hold up fingers for chords.