I'm sure you will be familiar with this next puppet if you have at any point been a child (which probably applies to many of us).
One of my very first encounters with puppets was with one similar to this, which my grandfather used to play with while singing "Pop, Goes The Weasel" and I absolutely loved it!
Whilst that in itself is a great musical experience for an early childhood/early primary class, there are a few other directions in which this puppet could take you.
A key part of the early Kodaly curriculum is ensuring that students can identify the differences between high and low pitch - if they cannot identify which note is higher out of two distinct pitches then they won't be able to progress to identifying so & mi or any other solfa.
The ability to accurately compare and contrast two or more sounds forms an integral part of the foundation of music learning. So let's have some fun with it!
There are a number of pitch comparison songs that I love to use with my students which ask them to respond to a sound or series of sounds which are either "high" or "low" (usually comparing two notes that are an octave apart, then a perfect 5th, then a minor 3rd as their skill progresses).
One such song is a classic called "Andy Pandy":
The teacher sings the song while students skip around the room (this is also a great lead-in song for talking about "skipping vs. walking music" as a precursor to simple and compound time signatures - the gift that keeps giving!). At the end of the song, the teacher will either sing "all jump up" or "all jump down" and students must respond accordingly, either on tiptoes with their hands in the air or crouched down on all fours.
After a few practice rounds, the teacher simply hums the last two bars of the song, to remove the verbal clues about whether it is a high or low sound being performed.
I also like to add a simple piano accompaniment - just alternating between chord I & V (D major and A major in this case) for each half-bar - to further challenge my students' auditory discernment. Be aware that this may not be the best idea if you have students with auditory processing difficulties or hearing impairments.
If you're looking for a fun hands-on activity to complete in class or with your own children, check out these instructions for making a pop-up puppet of your very own!