Coffee machine capsules for schools (4)
I believe the answer is:
pods
'for schools' is the definition.
(both can mean groups of marine animals)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for pods that I've seen before include "Groups of dolphins" , "some seals" , "Pea-jackets" , "From enclosed cabins" , "Seed cases" .)