ERIC is largest and best known database for research in Education. The EBSCO version of ERIC allows you to more easily search by subject heading, in the title, or in the abstract. ERIC will allow you to limit to specific grade levels. ERIC (EBSCO) will also provide a good (but not perfect) APA citation for each item you find.
APA PsycInfo is the largest and best known database for research in Psychology. APA PsycInfo allows you to limit to empirical research and by type of empirical research. APA PsycInfo will also allow you to search by subject heading, by age of population, within the title, and within the the abstract. APA PsycInfo will provide near perfect APA citations for each item you find.
Though Google Scholar should not your first choice for locating research - as it lacks the focus, sophistication, and power of ERIC and PsycInfo - Google Scholar is ideal for quickly locating articles found in a bibliography or reference list (Snowball Backward). Google Scholar also allows you to locate the articles that cite a particular article by clicking on the "Cited by" feature (Snowball Forward).