Naturalist Field School programs bring instructors to ACES from all over the country to teach and share their passion about the natural world. Courses range from Astronomy to Ecology, from Birding to Nature Photography, and so much more. The majority of our courses are offered in the summer months with a few programs in the winter and fall. We hope that you can join us for a day or a week of learning and sharing the appreciation of the natural world.

Tuition and Scholarship Information
Tuition is listed with each class description, and full payment is required to confirm your space. Please register early in order to ensure your participation.

ACES members receive discounted prices on all classes. Interested in becoming a member? Visit the Donate to ACES page now!

ACES makes a concerted effort to keep tuition affordable and also offers several partial-tuition scholarships — please download the scholarship application if you are interested. We also offer special discounts for accredited teachers — please inquire.

Call Jim at ACES for reservations: 970-925-5756

* To register online, click on REGISTER NOW button under each class
* To register over the phone, call:
970.925.5756 for Hallam Lake and Toklat (Aspen) classes
970.927.6760 for Rock Bottom Ranch (Basalt) classes
* To register the old-fashioned way, please download form and
Fax to: 970.925.4819 or
Mail to: ACES - NFS, 100 Puppy Smith Street, Aspen, CO 81611

We accept personal checks, Visa and MasterCard

Academic Credit
College credit is available for various adult classes through Colorado State University and Adams State College for an additional fee. Please inquire for details and confirm credit acceptance with your district or institution.

Refund Policy
ACES cannot return deposits due to last-minute cancellations. Refunds are given if the participant cancels at least two weeks prior to the start of the class. Half of the class fee will be returned if the cancellation occurs less than two weeks before the start of a class. A $10 fee will be charged for all cancellations. In an event that ACES has to cancel a class, full refunds will be issued.

For information on lodging options, call Stay Aspen Snowmass and the Aspen Chamber Resort Association at 1-800-598-2004. For campground information and reservations, contact the National Recreation Reservation Service at 1-877-444-6777.

You will be asked to sign a waiver if you are participating in any of our classes or programs. One waiver is good for all classes and programs that you take that calendar year. Please download a waiver, fill it out, sign it, and bring it with you when you come to your class.

ACES does not discriminate on the basis of race, color, national origin, sex, religion, age, disability, political affiliation, or familial status.