Are you sure you are not me last year?! I am going to give you my perspective and experience, I am not suggesting these are all your issues but just my story.....
I have high achievers. VERY different learning styles. DD did kinder last year at 4, she's always had a level of maturity about her. DS was 6 in 1st grade. I did NOT have enough schedule. They always had about one full hour more most days to play, do whatever before we started, and did not get up early enough. DD was usually fairy land with her dolls and DS was watching a lego scene on his computer, or building something new. They had a hard time getting in to school mode. We would do one thing, then DS basically whines/complains after taking yet another break to eat/play whatever and would talk about how he already did math, did this or that like it's acceptable to do ONE thing in an entire day LOL. I would start my lecture.....sometimes end up totally frustrated outwardly even, he would get upset in some way, I would lecture more etc etc. It was just not always so pleasant.
I realized he was very mature and above average in many areas, not necessary maybe genius by nature, but we take alot of time to work with them because I think kids are so much more capable than schools teach and i want them to have every opportunity. Well, I decided it was time he heard this. I sat him down, had a long talk about the difference between our home and kids who go to public school. I told him I love him, and I have decided instead of working or doing anything else, I feel blessed to be at home, being your teacher.....we talked about opportunities, how he has time to expand on things he enjoys, getting everything done during the day, having time for outings, no homework. Then we talked about the things he NEEDS to know and learn, such as a writting/reading program, math skills, basic stuff. I also talked about school being an option, but i think he has more opportunity learning at home and his day would be much longer, less time for extra things etc. Then I asked him to write me a list of 5 things he would like to learn more about during the year. Everything had to do with science/physics, and shockingly he said cursive writing. The very next day I changed tracks. I started using a version of the workbox thing, which at the time I didn't realize had a name and is all over the internet as means to organize your day. I couldn't give him 12 things, no way, but we started with 4 boxes. Every morning he could see what he needs to do. My DS NEEDS to see everything in advance. He does NOT do well with open endedness in any form. He needs to be able to see the whole day, I think it gives him a little security of not being suprised. DD h owever goes along with anything at any time, but she is very intensive, just different kiddos. So back to his list....I told him before cursive we just need to get through the handwritting without tears workbook for printing. I did not make him do it all, just enough to really refine some of his skills. He felt very proud to get his cursive book after. We started upping the science stuff but made it fun, project based.
I also decided I DO need a little separation in the roll department. I NEED to be more teacher mode during the day. For them and me in many different ways. As mom I feel emotional about his attitude or lack of, and I feel somehow responsible for them being happy every second. I do not react to attitude, I ignored the whining, complaining, never lecture about how this made me/us feel. AT first I had to ignore alot, then not so much, now it's totally gone. I would always remind him he may take his work to his room or outside, where he wants. At first sometimes he would carry on I think just wanting me to react. I would calmly tell him if we finish we can move on to (x), or if you feel the need to be outwardly upset I am asking you do it elsewhere because I am doing things too and it is very distracting. We do not reward/punish for schoolwork, it's just expected. I wouldn't take away the WII or play time, but it's going to be very short if he doesn't get it done because we will run out of time. I also realized his dad is a much better math teacher than I. He is helping me now to become more creative with my teaching math, but DS gets attitude when something is either too easy/boring/busy work, or he's not understanding. He does NOT like not understanding something. He also likes very plain text. Counting butterflies and coloring parts of things is NOT acceptable to him LOL. DD on the other hand needs that.
LIfe is so great now, I LOVE school with them. Honestly alot of it I think was the relationship we have during the day has changed a little, and the workbox idea. We are a very close family, my kids are very attached to me and DS especially feels very needing of my happiness to do well.
If you do not have some sort of workbox system I would highly recommend it. Basically you get them bins, and fill each with one thing so that can see ahead, and see their boxes finish. I think it gives them some control, and while I used to think I would be bombarding him with too much and freak out about "all the stuff he has to do" it is quite the contrary. I realized he NEEDS to see it all.
I'm truly enjoying homeschool now. And it's not like things were always miserable. Plenty of times he was a joy. Once we found a system that works everything changed. We also have nutrition/physical health as part of our learning daily and we set alarm clocks to be up at a good time for us and give us enough sleep. Since we do not have to catch a bus we are up a bit later than others and up at 8.