Chao Container #1
Near the start of the stage where you use the first pulley by the pile of wooden boxes, it’s just around the left hand side.
Chao Container #2
After the part where you use the springs to bounce down in a spiral through the cylcinder tunnel, you will see the Chao Container accross the gap with the hovering robots.
Chao Container #3
This container is hidden behind four other wooden boxes shortly after the bridge which has the floating section (and the middle rollers which you have to somersault through).