I am a public sector worker and we are all facing similar issues to the teachers and have in my career worked for both central and local government.
However, I don't support strikes because they simply do not work and the only people who are affected by them are the people we work to serve, whether that be children, benefit claimants, vulnerable people or general members of the public. Our lords and masters suffer a tiny bit of inconvenience and then go ahead and implement whatever changes the strike action is against anyway, while the people who are striking get a public bashing.
I would have much more respect for the union's if instead of moving to strike action, they went for a work to rule approach. They should press for industrial action that involves people working their contracted hours and to their job descriptions.
This would never happen in Local Authorities because workers tend to enjoy the 'perks' of things like flexi-time etc too much to agree to work to rule. I appreciate that teaching is slightly different, but I would support this type of industrial action in schools, even if it meant that my child's educations suffered for a more prolonged period than one day of strike action because it is more likely to have an effect. I would also be more likely to join the union in my field if they opted for this type of action rather than strikes.
Sure, 'work to rule' would take a while, but the system would break down from the inside out, meaning that our service users / customers / patients / children would be the last to suffer, not the first and our lords and masters would back down long before it ever got to that point anyway.