There are huge differences between how the police and teachers operate as government entities.

The biggest difference being inaction/underaction on the part of the unions. Police funding is simple. There's an "association" that lobbies on behalf of law enforcement, but it isn't strictly a union. So a lot of it is self-governing and regulating. The loudest single voice (with the most to offer) gets heard - The right legislator (who likes law enforcement, is known to be tough on crime) is approached, and asked to submit a bill improving funding. The normal conversations take place, exchanges of favors on the house/senate floors, etc. The bill is passed and money is doled out. The legislator gets to spend 20 minutes in the spotlight and admiring how little actual work they had to do to get some notoriety. Re-election is in the bag!

For teachers unions, there is committee after committee, negotiations, favors, petty politics, loads of compromises, and THEN it goes to a legislator. Unions in most other states get law firms and organizations specifically built around legislative negotiations to handle all of this. Not Arizona's teachers. Since the Teacher's union is voluntary and representative to teachers that aren't even members, the coffers are pretty dry most of the time.

Instead, they come to the table ready to play hardball. It COULD work out for teachers doing this, which is why they try in the first place. But what they don't get is that it's way too much work for that legislator and they'd rather just not bother getting their hands into something so wet and sticky as education funding. So, what negotiation DOES happen ends up getting rejected by one side or the other because the only thing good to come out of a popularity-based committee (like the AZ teacher's union) is the platypus.

I'm not saying unions are bad. Just that Arizona's Teacher's union is. If you have unreasonable (unfundable, etc) demands, you're not going to get anywhere.

Your best bet is to wait for the current administration to change, elect union board members that are competent, and work to be directly involved at getting collective bargaining established in the next session.