The Oklahoma State Science and Engineering Fair (OSSEF) is the premier STEM research competition for Oklahoma students in grades 6 through 12, and it is the state's official affiliate of the Regeneron International Science and Engineering Fair (ISEF).
The 69th annual OSSEF will be held Friday, April 2, 2027, at Oklahoma State University in Stillwater. In 2026, 204 students from 47 schools across 32 counties presented 169 projects, and participation grew 10% over the previous year.
You cannot sign up for OSSEF. Every competitor earns their spot by advancing from one of eight regional fairs, which means winning at the state level starts with a plan that begins months earlier, at your regional.
This guide maps the full route: which regional is yours, how the deadlines stack, and how Oklahoma's two separate paths to ISEF actually work.
Find Your Regional Fair First
Oklahoma's regional fairs are assigned by county, so your school's location decides where you compete. The eight regionals, per the OSSEF regional fairs page, are:
Regional Fair | Location | Counties Served |
|---|---|---|
Tulsa Regional Science Fair | University of Tulsa, Tulsa | Tulsa, Creek |
Bartlesville District Science Fair | Bartlesville | Nowata, Washington, Osage, Rogers, Pawnee |
Northeastern Oklahoma Regional | NEO A&M College, Miami | Craig, Delaware, Mayes, Ottawa |
Muskogee Regional | Muskogee | Muskogee, Cherokee, Wagoner, Okmulgee, Sequoyah, McIntosh, Adair |
Eastern Oklahoma Regional | Wilburton | Atoka, Choctaw, Haskell, Latimer, LeFlore, McCurtain, Pittsburg, Pushmataha |
East Central Oklahoma Regional | Ada | Carter, Coal, Garvin, Hughes, Johnston, Love, Marshall, Murray, Okfuskee, Pontotoc, Pottawatomie, Seminole |
Central Oklahoma Regional | Edmond | Oklahoma, Cleveland, Canadian, Payne, Logan, Kingfisher, Grady, Lincoln |
Northwestern Regional | Alva | Garfield, Woods, Woodward, Major, Alfalfa, Grant, Blaine, Dewey, Ellis, Harper, Beaver, Texas, Cimarron |
Regional fairs typically run in late January and February, and their entry deadlines land earlier still. Tulsa's registration, for example, has closed in mid-December in recent cycles. If you wait until spring semester to start, your season may already be over before it begins.
NAISEF
Oklahoma students who are members of federally recognized tribes have an additional opportunity: the National Advancing Indigenous Science and Engineering Fair (NAISEF), run by AISES, is a national ISEF-affiliated fair open to American Indian students across the United States. It is a separate application and pathway from OSSEF, and for eligible students it can be a second shot at international qualification in the same season.
Know Oklahoma's Two Routes to ISEF
OSSEF advances a small number of students to ISEF based on judging scores and recommendations, and only students in grades 9 through 12 are eligible for that advancement. Grades 6 through 8 can compete at OSSEF and qualify for the Thermo Fisher Scientific Junior Innovators Challenge.
Several of Oklahoma's regional fairs, however, are independently ISEF-affiliated, including Tulsa, Bartlesville, Eastern Oklahoma, East Central, Muskogee, Northeastern Oklahoma, and NAISEF. That means a strong high school project can earn an ISEF spot directly at the regional level, before OSSEF even happens. Students who advance to ISEF from a regional may still present at OSSEF, but they are not required to.
So if ISEF is your goal, treat your regional fair as your ISEF qualifier, not a warm-up. Bring your project at full strength in February, because the judges scoring you there may hold your ISEF ticket.
Build Your Timeline Backward From the Deadlines
OSSEF registration for 2027 opens February 1 and closes March 1 at 11:59 pm, with all required forms uploaded, no exceptions. Your regional deadline comes earlier, and any required approvals come earlier than that.
Your ideal timeline for a competitive project is:
Finalize your research question and experimental design by early fall,
Secure any required reviews and signatures before collecting data,
Run your experiment through late fall,
Spend December and January on analysis, your paper, and your board.
That leaves the weeks before your regional for presentation practice rather than last-minute data collection, which is where rushed projects fall apart.
Get Your Forms Right the First Time
Because OSSEF and its regionals sit inside the ISEF system, paperwork follows ISEF rules.
High school projects use standard ISEF forms, and middle school students in grades 6 through 8 may be able to use the simplified MS-EZ forms instead; confirm which set your regional accepts when you register.
Projects involving human participants, vertebrate animals, or potentially hazardous biological agents need approval before experimentation starts. Retroactive paperwork is the most common self-inflicted disqualification in ISEF-affiliated fairs, and no amount of good data fixes it.
Prepare for the Judges' Interview
At OSSEF and its regionals, judging is conversational. Judges will ask why you chose your method, what your data actually supports, and what you would do differently. The students who advance are the ones who can defend decisions, not just describe results.
Practice answering three questions out loud until your answers are sharp: why does this problem matter, why is your approach a valid way to test it, and what are the limits of your conclusion.
If you are in grades 9 through 12 and eyeing ISEF advancement, be ready to talk about next steps for the research too, since judges recommending students for international competition look for projects with room to grow.
Work With Coaches Who Have Won at ISEF With ScienceFair
Every step above is easier with someone in your corner who has already competed and won in the ISEF system. Our coaches help students pressure-test research designs before the paperwork is filed and rehearse the judging interviews. Students in our programs qualify for ISEF at an 89% rate against a national average of 2 to 5%.
If you are targeting your regional fair, OSSEF, or ISEF itself, book a free consultation to talk through your project and timeline with an academic advisor.
