We can use a tool called Audacity. You need download.
here you are how you can do it.
http://audacity.sourceforge.net

The first school will  record a rythm using "audacity",  students can use instruments, music, noises, their bodies... then it will be the turn of another school.

this  can be the order:

Mérida (Teresa)

Wexford

Mérida (Inmaculada)

Bialystock

Oradea

It would be good to say that we uploaded our rythm  and the following partner will be able to upload  his own rythm

I have mixed our students' voices and this is the result. I hope you enjoy so much like me.
I couldn´t find  the music folder of Dorota and Inmaculada. I have no problem to mix the music again  if you upload your students'  music.
If you want you can mix the music in another way, try it with your students and share it, it is very funny.

 

And here it is Dorota's