The Associate Certified Entomologist (ACE) exam is not an exam you can cram for. It tests for a wide body of knowledge, and preparation matters. ESA recommends a minimum of 40 hours of self-study, regardless of your experience level.
These are the main recommended study materials for the exam as well as a number of additional resources that can help prepare applicants.

NEW! The Official ACE Exam Prep Course by the Entomological Society of America

IPM for the Urban Professional
A Study Guide for the ACE

Ace the ACE Podcast
(Apple Podcasts, Spotify)

NPMA's ACE Exam Preparation Course

NPMA's Field Guide to Household Pests and App
Familiarity with information in these references, along with solid hands-on experience in the pest control industry, and participation in ongoing continuing education should adequately prepare prospective ACE candidates to take the certification exam.
Additional Resources
- Bennet, G., J. Owens, and R. Corrigan [eds.]. 1997. Truman's Scientific Guide to Pest Control Operations. 6th ed. Questex Media, Duluth, MN.
- Gold, R. E., and S. C. Jones [eds.]. 2000. Handbook of Household and Structural Insect Pests. Entomological Society of America, Annapolis, MD.
- Hedges, S. A. 1996. Field Guide for the Management of Structure-Infesting Flies. G.I.E. Publishing, Cleveland, OH.
- Hedges, S. A. 1998. Field Guide for the Management of Structure-Infesting Ants. G.I.E. Publishing, Cleveland, OH.
- Hedges, S. A., and M. S. Lacey. 1996. Field Guide for the Management of Structure-infesting Beetles. Vols. I (Hide and carpet beetles/ wood-boring beetles) and II (Stored product beetles/occasional and overwintering beetles). G.I.E. Publishing, Clevland, OH.
- Koehler, P. and Pereira, R. General Household Pest Control. University of Florida IFAS.
- Kramer, R. 1998. PCT Technician's Handbook. G.I.E. Publishing, Cleveland, OH.
- Mallis, A. 1997. (8th Edition) and 2004 (9th Edition) Mallis Handbook of Pest Control. G.I.E. Publishing, Cleveland, OH.
- Ware, G. W. 2000. The Pesticide Book. Thompson Publications, Fresno, California.