If I take my ex to court, will they change our child support?

Our child support was ordered a couple years ago, and now my ex changed jobs and says he makes less money. He also has a band and makes money off the books (he's also always going to concerts, buying new games, and new electronics). I have since lost my job, and now receive unemployment, medicaid, and food stamps for my daughter and myself. I've asked him to help buy my daughter's school clothes and supplies, but he refuses (even though I can't afford them). He says that the only thing he will do is give the exact amount the state said he was responsible for and not a dime more. My daughter is turning 5 in two weeks and he won't help with a birthday party (my parents are helping). He won't even make the 15 minute drive to our house to visit her, instead, I drive her to his grandmother's (half an hour away) twice a month, for the weekend, and he'll visit her for a couple hours once a month. So basically, I'm wondering even if they end up reducing the weekly amount I get, would they still make him help me buy her school clothes & supplies? And can they make him get dental insurance since she has none? And what about after-school activities?
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Child support is supposed to cover the needs of the child. Child support guidelines provide enough money for the child to maintain the same standard of living as an intact family. So, it is figured to cover school clothes, activities, supplies and birthday parties. Sounds like you want him to pay for the school supplies a second time around since it is already in the child support guidelines. You should get a two jobs so you can provide your share of money for your daughter instead of relying on welfare. It is a possibility that your always asking for money has made him bitter and now you will have a daughter without a father. Don't look up the statistics on that. It will scare you. I would recommend having the grandmother give him a little money to take the daughter places and spend more time with her. It would be better for her in the long run.
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