Introduction:
Worldwide, 40% of children are exposed to secondhand smoke. Therefore we need promotive efforts through health education media to improve children's health literacy.

Objectives:
The aim is to design health education media about secondhand smoke exposure as smoking media literacy for children.

Methods:
This research was designed to develop picture storybooks based on researchers’ focus group discussions and interviews. Focus group discussions were held with elementary school students aged 8-10 years to determine students' understanding of secondhand smoke exposure for children and the educational media needed to improve children's health literacy. The results of the analysis form the basis for researchers to design picture storybooks. The next step is to test internally with interviews with experts, including material experts, media experts, and linguists. Data collection instruments include focus group discussion guides and validation sheets. Furthermore, the data obtained is processed and analyzed using descriptive statistics as material for product revisions to make it suitable for use.

Results:
The design of a picture storybook entitled "Be Hero to Zero Smoke" was considered suitable for use as health education media for children based on the assessment results from judgment experts, material experts, media experts, and linguists. The contents of the picture storybook material design was according to the information needs of the informant children about secondhand smoke exposure and the steps in preparing children's stories. Furthermore, an internal test was carried out twice to learn if the picture storybook design is suitable for use. Improvements were made to cover pages, paper, fonts, paper layouts, images, characters, plots, language usage, and messages. Based on expert evaluation criteria, the final score of basic design categories by material experts was 87.8%, media experts 95.46%, and linguists 89%.

Conclusion(s):
Focus group and expert input on the design of picture storybooks about secondhand smoke exposure for children through internal testing with improvements met expert criteria and lays the ground for future external testing.