California Science & Engineering Fair
Affiliate Rules


No Constraints

The California Science & Engineering Fair (CSEF) imposes no rules on any affiliated fair as to the way in which they may be operated. We rely on each affiliate to determine how best to promote their fair and to select the best science fair projects. In particular:

We impose no rules on the grade levels of student participants.
However, it must be remembered that the CSEF admits only those students in grades 6-12, regardless of prizes won in affiliated fairs or grades included in a particular panel.
We impose no rules on the categories which affiliated fairs may use.
Some affiliates do, in fact, use the same categories, but this is by choice. Affiliated fairs with a significantly smalller number of projects than CSEF will probably find it to their advantage to use a smaller number of categories.
We impose no rules on the acceptability of team projects.
Some affiliates accept team projects, while others do not. Those who do accept team projects should be aware that the number of team members on projects accepted to CSEF is limited to three (3). Projects with N team members at the qualifying fair must have all N members included in the CSEF application. Changing the author list of a project between fairs is not permitted.
We impose no rules on the method of selecting qualifying students.
Each affiliated fair is the best judge of its own projects and is therefore the appropriate agency to determine the method of selecting qualifying and alternate projects to CSEF.

Please note that affiliated fairs which do not accept students in all grades accepted by CSEF, or which do not accept team projects, have thereby precluded the possibility for such students and projects from qualifying to CSEF, as we will not overrule affiliate decisions as to their selection of the best projects in their geographical domain.


The California Science & Engineering Fair does require that affiliated fairs be open to all students within their geographical domain, regardless of type of school attended: public, private, or home school. This includes students residing within the fair's geographical domain while attending an online school, regardless of the physical location of the online school’s registration. For qualification purposes the cognizant fair is the fair whose geographical domain includes the location where the student receives instruction. Each student in California therefore has one and only one affiliated fair through which he/she may qualify to CSEF.

The geographical domain of an affiliated fair may be a single county, or may include several counties. Fairs covering less than one entire county will not be recognized except as a temporary measure to enable new fairs to become established.

In return for this inclusiveness, CSEF guarantees not to recognize any fair other than the current affiliate within the same geographical domain.

Qualifying Authority

No more than one affiliate will be authorized to qualify students within any geographical domain to CSEF. The qualifying authority domain for each affiliate is included in our list of all affiliated fairs.

Most affiliates are county science fairs which uniquely have authority for students within their county. In those cases where affiliated county science fairs also feed into affiliated multi-county regional science fairs, the more local, or county, affiliate is the cognizant authority for qualifying all students within its geographical domain. Students who are qualified by their county science fair cannot lose that qualification by participation in any other affiliate. Similarly, students who were not qualified by their county science fair cannot gain a qualification by participation in any other affiliate. This policy refers only to the authority for qualifying students to CSEF and has no bearing on school or student participation in any and all other science fairs.

Nominating Winners to CSEF

The California Science & Engineering Fair is a competition among the best science fair projects in the State. To this end, CSEF does not constrain the method by which affiliates select their “best projects.” Entrants in the California Science & Engineering Fair establish eligibility through CSEF affiliates by satisfying two requirements:

Satisfaction of the the first requirement is not a guarantee of the second because each affiliate is limited in the number of projects which it may qualify to CSEF.

Many years ago CSEF set the requirement that students had to receive a first, second, or third place award, but this requirement was later found to be impractical given the diverse character of our affiliates. In practice now, some affiliates are able to qualify projects receiving honorable mention category awards, while some others may not be able to qualify more than half of their first place award winners, though both of these extremes are uncommon.

Important: There is no requirement that the number of projects qualified to CSEF must be balanced between categories in the affiliated fair. It is within the discretion of affiliated fairs to choose as many or as few from each of their categories so long as the total number of projects selected satisfies the maximum limit established. It may be more convenient administratively to select projects uniformly from all categories, but this is not required. If many excellent projects compete in one category, while another has few, CSEF encourages the selection of the best projects, regardless of category.

Reporting Requirement

The California Science & Engineering Fair requires that after each affiliated fair is completed, a list of all students (including the names of all students on each team project) who have been selected as eligible to apply to CSEF must be communicated to us. This list must include the names of all students participating in team projects, and should be comprehensive of all selected students — that is, it should not be restricted to those students who have already indicated a desire to enter CSEF. Such a restriction would require subsequent additions as students change their minds, an unwelcome administrative burden.

An Excel spreadsheet serving as a template for reporting qualifying and alternate students is available here.. However, if use of this template is not compatible with your fair’s abilities, other report forms will be accepted.

Questions regarding these rules should be sent to

Last updated: Tue Feb 6 09:51:59 PST 2018
California Science & Engineering Fair / Affiliates / Regulations /