This is the 13857th most frequent Korean word.
만들면서
"While making" or "while creating."
In this sentence, '만들면서' is used to describe an ongoing action ('making rice cakes') during which another action ('called a friend') occurs.
나는 떡을 만들면서 친구에게 전화했다.
I called a friend while making rice cakes.
Here, '만들면서' indicates the context of learning that happened during the activity of 'working on a project'.
그는 프로젝트를 만들면서 많은 것을 배웠다.
He learned a lot while working on a project.
In this case, '만들면서' shows the simultaneous occurrence of demonstrating creativity and the act of 'making toys' by the children.