How I Use It
I don't have first-hand experience but I remembered my teacher used this website to teach her class. If I remembered correctly, it started really easy and become challenging after. I would let students use the website by themselves and let them work at their own pace. I would let them collaborate with each other first if they are stuck on something.
I believe this is a great tool for children that are interested in learning Computer Science. It's too easy for students that previously have coding experiences but it allows the students to at least think like a programmer. I believe they need more hints for some of the exercises because I remembered I was doing the advanced questions and I got stuck on them. My teacher doesn't know how to solve it so it was a really frustrating experience to figure it out.