The Esperanza College Associate of Science in Natural Science at Esperanza College focuses on providing students with a solid academic foundation, including such hands-on experience as lab work and field activities, to continue on to a four-year science degree.

The program offers rigorous courses in life and physical sciences, including biology, chemistry, and physics. Students learn about cells, atoms, and molecules to understand larger concepts and laws, such as the biological hierarchy and how macromolecules work or the laws of thermodynamics. They also develop a scientific understanding of present issues, including global warming and becoming better citizens.

The classes are taught by excellent professors in state-of-the-art facilities, enabling students to develop the skills necessary to succeed in the lab and in the classroom. The student’s faith and religious thoughts are also called upon to reflect on scientific realities. Students have the opportunity to discover and articulate how their faith life enlightens their chosen academic pathway. They also take courses in math and the humanities, to further develop their abilities to solve problems and think critically.

Whether your goal is to discover a new medicine or a new source of renewable energy, save a patient, rescue an endangered species or protect the rainforest, a degree in science is your first step.

Program Student Learning Goals
  • Establish a foundation of analytical thinking, specific skills, and competencies in the basic sciences needed by professionals in the area.
  • Apply the knowledge students have gained to be effective professionals in their desired science related career.
  • Be equipped for success through educational, social, and spiritual enrichment experiences.

All science classes include hands-on laboratory work. Our laboratories are equipped with state-of-the art technology. Through wonderful collaborations with well renowned organizations in the area, students have the opportunity of doing summer research and participate in a variety of activities. They can also act as mentors in our science summer camps.

After graduation from Esperanza College, students are well prepared to transition into Eastern or any other university to complete their bachelor and beyond.


Nilsa Graciani, Program Director

Nilsa Graciani, Program Director

PhD, Organic Chemistry, Texas A&M University
BS, Concentration in Chemistry, University of Puerto Rico, Rio Piedras

Dr. Nilsa Graciani joined the team at Esperanza College in July 2011 as an Adjunct Professor. In October 2013 she assumed the position of Director for Middle Level Education, Math and Science, and currently serves as the Director of STEM and Medical Assisting.

Prior to her work at Esperanza, Dr. Graciani held research scientist positions in the pharmaceutical industry. Her research included work with peptides and small molecules in various therapeutic areas including cancer, cardiovascular, inflammation, infectious diseases and women’s health. She has been a speaker at scientific and health conferences.

Professor Graciani lives in Garnet Valley, PA with her husband and three children. She is actively involved at her church. She is on the Advisory Board of the Young Professionals Network at the Greater Philadelphia Hispanic Chamber of Commerce and the Fox Chase Cancer Center Community Advisory Board.  She also serves on the Occupational Advisory Board of two local high schools. In 2019 her role expanded to Chief STEM Officer at Esperanza where she identifies and leads opportunities for the youth at Esperanza and the surrounding community.  Her work allows her to impact younger generations by sharing her passion and developing in them a love for becoming professionals in STEM and health related fields.

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Javier Arce-Virreira

Javier Arce-Virreira

PhD, Texas A&M University
MS, Penn State University
BS in Chemical Engineering, Colorado School of Mines

Javier Arce-Virreira worked in the food, petroleum, and chemical industry in Bolivia and the United States.  His main achievement was patenting new frying methods for potato chips.  He also designed and built soybean and dairy plants.  Recently he worked in Wyoming mining sodium carbonate.

He loves teaching and have done it for the past ten years.  For him, instruction is not only transferring information; it is also giving insight and showing practical uses.

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