His refusal to provide you with the copies of the education IRA per the court order (once your agreement was signed off on by the judge, it became a court order) is contempt of court. So is not paying the extracurricular activities.

What you can do is file contempt of court charges against him. Here is what you can ask for:

That you are put legally in charge of the IRA. You will need a very specific court order for this.

Your legal fees.

That he pays you his portion of the extracurricular activities.

How is the tax exemption handled? If it is alternated or he gets it every year, you can ask that he doesn't get it if he isn't current on ALL of his financial obligations by 12/31 of any year. That may be an incentive for him to pay what he agreed to.