I agree that having more kids doesn't make you more patient. I do think that you need to control your kids better. However, the yelling just makes them act crazier, C.. You need to stop the yelling - they are totally desensitized to it. You need to childproof your house - no wooden boards around for them to play with. And you need to supervise them more.
A daycare has a strict schedule for the kids. They have toys that are played with and then put away. They eat at the same time every day and they have to go down for naps after playing outside in the afternoon. You should institute the same kind of strict schedule for your kids. That means instituting a strict schedule for you. In the morning, get up before the kids. Make your bed and get dressed for the day. While they are eating breakfast, throw a load of clothes in the washer. Have them bring you their dishes and "help" you clean up the kitchen. Put a little art project on the table while you finish up, and then go to the next thing, whether it's trains or puzzles. Don't let them start another toy set without putting up the first one. Play MUSIC on the CD player (NOT the TV) while they are playing.
If they start fighting over a toy, put the toy in time out. And MEAN it. No giving back a toy you took away. IGNORE them wanting the Goodwill toys - I really mean it. While they are playing in a room, use the time to dust that room and put anything that doesn't belong in a basket or box to be carried around to other rooms later on. When it's time to clean up to transition to the next activity, get them to help you vacuum the floor. They will love that. Move to the next room you need to clean and give them a new set of toys to play with.
Make reading books part of your day several times. Get them outside to play - maybe when you need to do some paperwork that you can take with you. They should NEVER be alone with the dog. EVER. The dog experts will tell you that - not just other moms. If one of them is taking the dog collar off and putting it around the other child's throat, that means you aren't supervising properly. This is a safety issue and you just have to do it, even if you think you can trust the dog.
Put the kids down every day for quiet time, even if they don't sleep. Hopefully they have separate rooms.
When they do stuff that is off limits, they need a swift and firm consequence. Make the consequence fit the crime. ALWAYS separate them if they fight, no matter who started it. If you are consistent about it, they will get tired of being separated and they will police each other to not fight. It is your job to keep them in the area of the house that you want them to be in - they should not have cart blanche in having the run of the house. Keep doors locked if you need to. More than anything, tell them what they are supposed to be doing. Without the yelling.
If you are calmer, it will be easier for them to be calmer. When they are immersed in an activity you have started with them, it's easier to run into the laundry room and get the clothes out of the washer and throw them into the dryer. Have what you need to take upstairs in a basket ready to take up with you when you bring your kids upstairs so that you aren't running back and forth and not supervising them.
It gets easier when you put them in preschool or kinder. Right now, treat your home like a daycare and supervise with a strict schedule. And NO YELLING.
You can do this. I promise you that it will get better if you do.
Dawn