Taught how to go in opposite ways at once! (5)
I believe the answer is:
shown
'opposite ways at once' is the definition.
I can't judge whether this definition defines the answer.
'taught how to go in' is the wordplay.
'taught' becomes 'sn' (I can't justify this - if you can you should give a lot more credence to this answer).
'to go in' means one lot of letters goes inside another.
'sn' going around 'how' is 'SHOWN'.
Can you help me to learn more?
(Other definitions for shown that I've seen before include "Displayed" , "Exhibited" , "Demonstrated" , "Explained" .)