1. pre-k or preschool* or nursery school* or early education or kindergarten
parent* or caregiv* or mother* or father* or famil*
emotional develop* or psychological develop* or mental health develop* or social develop* or cognitive develop* or physical develop*
Access (health literacy/outside play)
health litera* or health education or health knowledge or health information or health understanding
outside or outdoor* or nature or wilderness or playground
play* or recess
Theses and Dissertations can provide a wealth of information including references to other studies and things like surveys, questionnaires, and IRB statements.