i need help

You didn't say if you have a partner in this and if that person helps out with this. My hubby thinks his job is to play with the kids so I was the disciplinarian. You have to get tough. You have to be the parent and get control. Stop being nice. Don't cry in front of them and mean what you say when you say it. If you tell them to do something and they don't, punish them and mean it. Don't back down. At the ages they are it will only get worse. They will be completely uncontrollable when they are teenagers if you don't get a handle on this NOW. The main thing is that you remain calm and strong. They won't respect you if they know they can push you around. Respect is the key here. My in laws and parents both accused me of being too tough on my kids when they were little but I could take them anywhere and not worry that they would destroy things AND they respect me now (they are 21 and 18) and I trust them to do the right thing. My sister-in-law accused me of being too tough and her son is now 13 and WAY out of control. She finally told my husband (not me of course) that I was right about being so tough. Get tough.

:flowerforyou: Yikes! My advice is to have a consistent daily routine so that the kids know what to expect every day and keep them as active as possible. Make sure they know what behavior is expected of them and what isn't acceptable, and what the consequences will be for bad behavior (I choose not to spank, but instead use punishments like grounding from TV or computer for a period of time) - and be consistent and follow through.
If you are getting so frustrated that you are shaking, try to (safely) separate yourself from the situation, at least briefly if possible, before it escalates, and ask for help.
And don't forget to make time for yourself! Good luck!

Here is a good web site with advice, http://familydoctor.org/online/famdocen/home/children/parents/behavior/368.html

I particularly liked this list:

There's not just one right way to raise children. And there's no such thing as a perfect parent or a perfect child. But here are some guidelines to help your children grow up healthy and happy:

Show your love. Every day, tell your children: "I love you. You're special to me." Give lots of hugs and kisses.
Listen when your children talk. Listening to your children tells them that you think they're important and that you're interested in what they have to say.
Make your children feel safe. Comfort them when they're scared. Show them you've taken steps to protect them.
Provide order in their lives. Keep a regular schedule of meals, naps and bedtimes. If you have to change the schedule, tell them about the changes ahead of time.
Praise your children. When your children learn something new or behave well, tell them you're proud of them.
Criticize the behavior, not the child. When your child makes a mistake, don't say, "You were bad." Instead, explain what the child did wrong. For example, say: "Running into the street without looking isn't safe." Then tell the child what to do instead: "First, look both ways for cars."
Be consistent. Your rules don't have to be the same ones other parents have, but they do need to be clear and consistent. (Consistent means the rules are the same all the time.) If two parents are raising a child, both need to use the same rules. Also, make sure baby-sitters and relatives know (and follow) your family rules.
Spend time with your children. Do things together, such as reading, walking, playing and cleaning house. What children want most is your attention. Bad behavior is usually an attempt to get your attention.

I commend you for talking about this, and asking for help.

Your success on MFP shows you are a strong and determined person.

I agree with the other comments about consistency and being the parent, not the "friend".

As for summer, wear them out! Keeping active will help both with your health and with keeping them busy and too tired to fight, whine, etc.