The kids look great, you engaged them and got them smiling, etc. I'd think about the perspective. If you want to have something like the bush in the photo how much should it obscure the kids? Go out and practice without kids and think about how to set it up, how will the background/foreground look in the photos? too much brick? not enough? too close to the top of the frame maybe? The brick in these creates lines leading out of the frame, from the head of the subject in the first one going both directions.
Practice seeing everything in the viewfinder. Your photos look like you're seeing the subject but not necessarily the backgrounds. Think about how you might need to change your vantage point - learn to see, and then move your feet (yourself) and change the vantage point. I want to take a step to the right to get the kids' feet in the picture (especially a little girl wearing cute shoes).
Your photos look like there's been improvement and I'd suggest more practice time, just you and your camera, thinking about what's in the frame before you press the shutter button. Think about what do you see? where do you see lines and shapes etc.? and how will that work in a portrait? Which way looks better if you change your vantage point? a step left or right? closer or farther back? With practice it gets to the point that you don't have to consciously think about it so much and you'll get better at framing shots and using backgrounds and foregrounds and get better compositions.