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Join Our Annual Catch-A-Thon!
Join Girl Scout Citizen Scientists from all around the world as we join forces to contribute to Alzheimer’s research by playing Stall Catchers during Citizen Science Month!
Our 5th Annual Catch-A-Thon kicks off April 20 at 12 a.m. EST / 6 a.m. CET / 2 p.m. JST and runs through April 26 at 12 a.m. EST / 6 a.m. CET / 2 p.m. JST.
Once again, the winners of our Catch-A-Thon 2026 will receive some fabulous prizes, so be sure to log in and start racking up those minutes catching!
Here are the prizes up for grabs this year:
- The top three countries with the most time logged playing during our Catch-A-Thon period will be featured on our website.
- The single country with the most time logged playing during our Catch-A-Thon period will receive a set of Field Guide to Citizen Science: How You Can Contribute to Scientific Research and Make a Difference books (7 total- one for each program grade level Daisy-Ambassador and an extra for the OCMT), a digital trophy and, of course, bragging rights as the winners until next year's Catch-A-Thon.
- The top five individual catchers will win a STEMinist notepad and pencil.
- ALL Girl Scouts who log 100+ minutes playing the game will earn the exclusive Girl Scouts & Stall Catchers patch for FREE!
- New this year: Players who have already earned the patch and log an additional 100+ minutes (for a total of 200+ minutes) will receive a special commemorative 5th year anniversary rocker.
We can't wait to see who makes our Hall of Fame list this year!
Learn More About Stall Catchers
Did you know… Citizen Science is one of GSUSA’s (inter)national service projects?!? USAGSO is excited to help our girls explore citizen science and contribute to Alzheimer’s research by partnering with Stall Catchers throughout the year.
How can you play a part in solving some of the biggest problems facing our planet? Enter citizen science, where volunteers help scientists collect data for their studies and experiments. Anyone can be a citizen scientist—all you need is curiosity and a willingness to help!
Stall Catchers is an online game that anyone can play - no experience necessary. In the game, you look at movies from the brains of mice and try to identify vessels as flowing or stalled. This helps to speed up Alzheimer's Disease research at Cornell University. Anyone can play this online game — no experience necessary. Currently, catchers range from 6 to 88 years old. A large part of the Stall Catchers community includes middle school students, seniors, caregivers and even Alzheimer’s patients themselves.
Get started catching today! Sign up and join a USAGSO team in 5 easy steps:
- Head to https://stallcatchers.com/ and click the orange, ‘Join now!’ button.
- Choose a username and enter your e-mail address, then click the orange, ‘Sign up’ button. Be sure to watch your e-mail for instructions on setting your password.
- Once logged in, click on your name in the top right corner and then select ‘Teams.’
- Type ‘USAGSO’ in the search bar – once you see your country on the list, click it!
- And, finally, click the green, ‘Join’ button to do just that… Join!
Learn more about Citizen Science and explore other exciting projects with our friends at SciStarter. If you have any difficulties signing up, please contact us at: overseascustomercare@girlscouts.org.
Play the Game to Earn Your Patch
The game is easy to grasp! Stall Catchers provides lots of helpful info to help you get started. Don't worry about making mistakes — each blood vessel is analyzed by multiple catchers, which ensures reliable crowd answers are generated in the end.
Girl Scouts who log 100-minutes playing the game will earn the exclusive Girl Scouts & Stall Catchers patch, FREE while supplies last!
2025 Catch-A-Thon Hall of Fame
In November 2025, 46 Girl Scouts in 10 countries on four continents made a huge impact on Alzheimer's research as part of a Citizen Science Project with Stall Catchers. In total, we accomplished 206 hours of lab-equivalent research. Thank you to all who participated and congratulations to our winners!
Here are the winners of our challenge!
🏆 Top Countries:
1. United States of America
2. Greece
3. Germany
4. Portugal
5. Mexico
🏆 Top Catchers:
1. Sparkle
2. Crazy Axolotl 2
3. AK Take Action
4. Shadowstar Valencia
5. Melody 091266
Check out this recap of everything we accomplished during our 2025 Catch-A-Thon!
