Become involved and bring in teachers' union (3,4)

I believe the answer is:

get into

I'm a little stuck... Click here to teach me more about this clue!

'bring in teachers' union' is the definition.
I can't tell whether this definition defines the answer.

'become involved' is the wordplay.
'become' becomes 'get' (synonyms).
'involved' becomes 'into' (I've seen this in another clue).
'get'+'into'='GET INTO'

'and' is the link.

Can you help me to learn more?

(Other definitions for get into that I've seen before include "Become involved with" , "enter" .)

I've seen this clue in The Irish Times.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.