Here are a few of my boys’ favorite informational texts:
Books by Gail Gibbons are great too. She does many animal books as well as books about holidays and seasons. They are written in a narrative format so they are easy to read and she uses a lot of text features that help kids learn information from the pictures.
Seymour Simon is another well known informational text author. His might be a bit above your youngest ones but we like to get them and use the text features to read them or my husband and I will explain the concepts. The boys love the photographs so they are still very interested.