OTA Dynamic Staff

***OTA’s Dynamic Teaching Team of 2017-2018 ***

Kindergarten Teacher: Alexandra Halverstadt

Education:  Ms. Halverstadt earned a Bachelor’s Degree in Business Administration (with minors in Psychology, Communication Studies, and Marketing) from University of San Diego. She later earned a Master’s Degree in Elementary Education from Grand Canyon University.

Teaching Experience: Ms. Halverstadt was a long-term substitute at OTA in kindergarten during the 2015-16 school year. She then became OTA’s kindergarten teacher beginning in the 2016-17 school year. Before her OTA experience, she was an instructional assistant at a school in National City and a substitute teacher for TK-6th grade at various schools in San Diego, Del Mar, and Solana Beach. Ms. H also has experience as a camp counselor, sports coach, tutor, nanny, and mentor.

Hobbies: Taking her dogs to the beach, paddleboarding, hiking, golfing, playing beach volleyball, photography, and spending time with family and friends.

Favorite Books/Things to Read: Anything by Dr. Seuss or Roald Dahl.

Favorite Subject(s) in School: Reading and Math.

Fun Fact: Ms. Halverstadt won a car at a Diamondbacks baseball game when she was 10 years old. It’s too bad that she wasn’t old enough to drive it.

email: [email protected]

Kindergarten Classroom Blog


1st Grade Teacher: Jenny Blackwood


Education: Mrs. Blackwood attended Towson University near Baltimore, Maryland. Mrs. Blackwood received her Bachelors Degree (Major: Elementary Education and Minor: Instructional Technology/Library Media Education) in May of 2006.

Teaching Experience:  First Grade Teacher in Silver Spring, Maryland 2006-2009, First Grade Teacher and Reading Specialist in Denver, Colorado 2010-2013, Librarian and Media Specialist (K-5) in Richmond, Virginia 2013-2015.

Hobbies: Practicing Yoga, Making Jewelry, Playing Beach Volleyball, Singing Karaoke, and Doing Crossword Puzzles

Favorite Books/Things to Read: The Secret Garden by Frances Hodgson Burnett

Fun Facts: Mrs. Blackwood won a car on the  December 15, 2016 episode of Let’s Make a Deal! Also, she was born on Independence Day, so she watches fireworks every year on her birthday!

email: [email protected]

First Grade Classroom Blog


2nd Grade Teacher: Lisa Pendleton


Education:  Ms. Pendleton graduated from Boston University in 2007 with a B.A. in International Relations. She completed her M.A. in Early Childhood Education at the University of Massachusetts, Boston.

Teaching Experience: Ms. Pendleton taught in Boston Public Schools for 6 years. She taught kindergarten from 2009-2013 and first grade from 2013-2015.

Hobbies: Snowboarding, traveling, yoga, running

Favorite Books/Things to Read: Travel writing, or historical fiction. Anything by John Steinbeck, Kurt Vonnegut, or Ken Follett.

Fun Facts: Ms. Pendleton took last school year off to travel. She completed a 4 month road trip and visited 29 states. Her favorite stops include the Grand Canyon, the island of Kauai, Yosemite National Park, Bryce Canyon, and any ski resort in Colorado!

email: [email protected]

Second Grade Classroom Blog


3rd Grade Teacher & Vice Principal of Curriculum & Instruction: Diana Han Pham


Education: Valedictorian, B.A. from U.C. Berkeley. She earned her Masters in Education and her CA Teaching Credential from University of San Diego, and cleared her credential at U.C.S.D.

Hobbies: Blogging about the S3G, camping, hiking, being outdoors/sun-soaking, folding origami stars (her trademark), dancing, writing poetry, spending time with
her husband and son.

Favorite Books/Things to Read: The Lord of the Rings Trilogy, The Alchemist.

Fun Facts: Loves Yosemite National Park where her husband, Paul proposed at Vernal Falls (one of her students thinks she lives in Half Dome). Mrs. Pham is a Black Belt in Tae Kwon Do. She served briefly as a Director of Education for a large corporation, but came back to what she loves: working in the primary grades! Nickname: Snoopy

Teaching Experience: Taught grades K-5. Taught pre-algebra & algebra grades 6-7. Ten years of full-time teaching. Ninth year teaching the Core Knowledge curriculum.. Taught in Seoul, Korea for a year after college working as an Education Coordinator training teachers & developing curriculum.

email: [email protected]

Third Grade Classroom Blog

email: [email protected]


4th Grade Teacher: Chelsea Rothman


Education: Ms. Rothman has her Bachelor’s Degree in Elementary Education from Towson University. She is certified to teach in New Jersey, Maryland, and California.

Teaching Experience: Student teaching experience with 1st and 4th grade. Ms. Rothman has taught 3rd grade for four years in a Baltimore City public school. She has been a camp counselor, dance teacher, and drama club coach.

Hobbies: Going to the beach, reading books, traveling, and spending time with my family and friends.

Favorite Books/Things to Read: The Magic Tree House Series, Where the Sidewalk Ends, and any mystery/thriller type of novel.

Favorite Subject(s) in School: Reading and Writing

Fun Facts: Performed in the Orange Bowl half time show in 2008. Ms. Rothman also did a cross country road trip through 13 states to get to San Diego!

Fourth Grade Classroom Blog


5th Grade Teacher & Vice Principal of Student Success: Sarah Cook

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Education: Mrs. Cook graduated from Vanguard University of Southern California with her Bachelors degree in Liberal Studies with an emphasis in Mathematics. She received her teaching credential and Masters in Education from Azusa Pacific University. 

Teaching Experience: Mrs. Cook spent the last 6 years working in classrooms throughout Southern California. Mrs. Cook received a wide variety of classroom experience through substitute teaching, tutoring, teaching literacy, leading intervention reading groups, and learning from veteran teachers. Prior to teaching at OTA, Mrs. Cook taught 2nd and 3rd grade in Rancho Cucamonga, California. 

Hobbies: Cooking, baking, reading, and playing with my dog Charlie! 

Favorite Books/Things to Read: Wonder by R.J. Palacio, Love Does by Bob Goff, any book that challenges me and helps me grow.

Fun Facts: Miss Rock recently changed to Mrs. Cook! She recently got married to Billie and they are loving life together!

email: [email protected]

Fifth Grade Classroom Blog


6th-8th Grade Social Studies Teacher: Jennifer Church


Education:  Miss Church graduated from California State University, Chico with a Bachelor of Arts in Liberal studies and a minor in Child Development.  She then went on to California State University, San Marcos where she received her Multiple Subject Teaching Credential.

Teaching Experience:  OTA 6th grade 2014-2015. 1st grade intern, K-5 robotics coach, and sub. At OTA 2012-2014. Miss Church also has been teaching swim lessons for 4+ years.

Hobbies: Miss Church loves the outdoors: swimming, biking, dancing, hiking, sprint triathlons. Miss Church also loves dancing, music, arts and crafts.

Favorite Books/Things to Read: mystery novels

Favorite Subject(s) in School:  Math and History (even though it was hard for her to remember dates and names, she loved learning about different cultures and history)

Fun Facts: Miss Church loves the water.  She grew up swimming and boating.  While attending Chico State, Ms. Church spent a summer in Pennsylvania teaching sailing at a camp in the Poconos.

email: [email protected]

Sixth Grade Classroom Blog


6th-8th Grade English/Language Arts Teacher: Turner Watts


Education: Mr. Watts earned a Bachelor of Arts degree in Education from Shepherd University in West Virginia.

Teaching Experience: Prior to joining the OTA team in 2014, Mr. Watts worked in the Los Angeles and Baltimore school systems teaching seventh and eighth grades.

Hobbies: Hiking, camping, reading, cooking, finding new places to eat, travel, board games, writing, playing with my dog Boh

Favorite Books/ Things to Read: The newspaper, anything by Bill Bryson, anything by John Grisham (guilty pleasure), short stories by Edgar Allan Poe, historical works, favorite novel hands down: Herman Melville’s book on Captain Ahab and that white Whale!

Fun Facts: Mr. Watts was in the Navy for five years and worked on a nuclear powered submarine. He completed four six-month deployments and visited nearly a dozen countries during his time at sea. He says the OTA project trees and checklists remind him of the “system mastery checklists” (qualification cards) submariners are given and asked to master before they earn the right to wear the Dolphins and stand a watch.

email: [email protected]

Seventh Grade Classroom Blog


6th-8th Grade Math Teacher: Gabriel Solis


Education: Mr. Solis earned his Bachelor’s Degree from Providence College. He majored in Social Science and minored in Accounting and pursued a career in education upon graduation. After volunteering for a year through a program called City Year, Mr. Solis went on to earn his Master’s Degree in Secondary Education with a concentration in Mathematics at the University of Massachusetts – Boston. He is certified to teach in both Massachusetts and California.

Teaching Experience: Mr. Solis taught 8th grade math in Massachusetts for three years prior to moving to San Diego. In San Diego, Mr. Solis taught 6th, 7th, and 8th grade math at a different charter school prior to joining OTA.

Hobbies: Mr. Solis is an avid sports fan. He is aware that Boston is the sports hub of the world and looks forward to letting his students know this. He enjoys playing basketball, tennis, baseball, running, hiking, among activities.

Favorite Books: The Bible

Favorite Subject in School: Math and Science

Fun Facts: Mr. Solis has driven across the country two times! He drove to San Diego from Portland, Maine in December and then in July for the big move. He speaks Spanish fluently and enjoys traveling.

email: [email protected]

Eighth Grade Classroom Blog


 STEM Teacher: Taylor Schlose


Education: Miss Schlose earned her Associates Degree in Social and Behavioral Sciences from Mount San Antonio College. She went on to complete her Bachelor’s Degree in Elementary Education at Northern Arizona University in Flagstaff, Arizona. She has teaching credentials in both Arizona and California.

Teaching Experience: Miss Schlose has taught Science for grades Kinder-6th. She taught 5th and 6th grade in Phoenix, Arizona for two years before coming back to California to teach 4th grade.

Hobbies: Miss Schlose enjoys sculling, biking, hiking, going to the beach with her dog Tucker, reading, knitting, baking, and crafting.

Favorite Books: The Hobbit by J.R.R. Tolkien, The Harry Potter Series, The Sherlock Holmes Books, and historical fiction/mysteries.

Favorite Subject in School: History and Science.

Fun Facts: Miss Schlose rocks at trivia games and has a knack for remembering fun facts! She visited 6 different countries in high school as a student ambassador to the United Nations and used to build and race solar powered boats!

email: [email protected]

STEM Classroom Blog


Instructional Aide: Krista Exerjian


Education: Bachelor of Arts in Psychology from the University of California, Santa Cruz in 2013

Teaching Experience: This is Krista’s second year working at OTA. Before, she worked as a Behavioral Interventionist within the Autism community. Before that, she worked at an aquarium and educated children and adults about the importance of our oceans! Krista grew up within the speech language community and was instilled with a passion for teaching children at a young age. She loves working with children and helping them learn!

Hobbies:  Running, hiking, reading, coloring, spending time outdoors and hanging out with her family.

Favorite Books: The Lorax by Dr. Seuss, Good Omens by Neil Gaiman and Terry Pratchett, The Art and Zen of Motorcycle Maintenance by Robert M. Pirg, The Five People You Meet in Heaven by Mitch Albom and The Help by Kathryn Stockett

Fun Fact: Krista has traveled to 14 countries, including: Norway, Sweden, Denmark, Lithuania, Estonia, Russia, Finland, Germany, the Czech Republic, Mexico, Belize, Honduras, Peru and Chile. She loves to travel and learn about different cultures!

email:[email protected]


Instructional Aide: Michelle Klim

Education: Ms. Klim earned a Bachelor’s Degree in Early Childhood Education with a minor in Psychology from Salisbury University in May of 2013.

Teaching Experience: Ms. Klim was a preschool teacher in New Jersey from 2013-2015. When she moved to San Diego, she taught preschool at Sacred Heart Academy from 2015- 2017.

Hobbies: Going to the beach, camping, hiking, taking yoga classes, and cooking. 

Favorite Books/Things to Read: Suspenseful Novels

Fun Facts: Ms. Klim studied abroad in Bologna, Italy for a winter semester and fell in love with traveling and the Italian culture! 

email:[email protected]


Instructional Aide: Jade Talbott

Education: Ms. Talbott attended Southern Illinois University in Edwardsville, Illinois. She received her bachelor’s degree in Elementary Education in May of 2016.

Teaching Experience: Throughout college, Ms. Talbott taught in 1st, 2nd, 3rd and 4th grade classrooms. After graduation, Ms. Talbott taught kindergarten at Eagle College Preparatory in St. Louis, Missouri for the 2016-2017 school year.

Hobbies: Ms. Talbott loves going to the dog park and beach with her corgi, Baauer. She also enjoys baking cookies and cupcakes.

Favorite Books/Things to Read: Don’t Let the Pigeon Drive the Bus! by Mo Willems and Teal (A Book about a Little Crayon that Makes a Big Difference) by Renee Galvin 

Favorite subject(s) in school: Reading and phonics.

Fun Facts: Being born and raised in the St. Louis area, Ms. Talbott is a Cardinals baseball fan. (Sorry Padres!)

email:[email protected]


Spanish Teacher: Cynthia Ostrowski


Education: Mrs. Ostrowski earned her Associate Degree from San Diego City College.  She received her Bachelor’s degree from Ashford University .  She majored in Social Science with education concentration.  She received her Masters of Cross cultural Education and her California teaching credential from National University.

Teaching experience:  Mrs. Ostrowski spent the last 5 years working full-time for the San Diego School District as a Spanish teacher/visiting teacher.  She was worked at King Chavez High School, Sherman Academy, Kate Sessions Elementary, Pacific Beach Middle School, and Chavez Elementary.

Prior to moving to San Diego she created a Spanish enrichment program at Northside Elementary, Cool CA (2007-2010). She was also  a Spanish tutor at Golden Sierra High School, Garden Vally CA (2007-2010).

Hobbies: Mrs. Ostrowski loves the beach.  She enjoys salsa dancing, biking, surfing, kayaking, paddle boarding, yoga and walking her three dogs.

Favorite Books/Things to Read: Cien años de Soledad by Gabriel García Marquez. Books by Alma Flor Ada and Mario Vargas Llosa. Favorite subject in school: Foreign language and World History.

Fun Facts: Mrs. Ostrowski has a big heart for animals.  She, along with a group of friends created a refuge place for stray dogs in Lima, Peru. She funds sterilization campaigns over there as well.

email:[email protected]

Spanish Classroom Blog


Music Teacher: Ellyn King


Education: Ms. King earned both her Bachelor of Arts and Teaching Credential at University of California, Los Angeles. She majored in Music Education, with an emphasis in Clarinet Performance, and has pursued extensive studies in Ethnomusicology.

Teaching Experience: This is Ms. King’s first year running her own music program but she has previously taught as Bret Harte Middle School, Lincoln Middle School, and Nora Sterry Elementary in Los Angeles. She has also worked at a music coach at San Marcos High School in San Diego.

Hobbies: Ms. King loves being outside! Hiking, backpacking, and rock climbing are some of her favorite things to do. She also likes dancing and enjoys playing banjo in her free time.

Favorite Books/Things to Read: Harry Potter, Lord of the Rings, Hitchhiker’s Guide to the Galaxy, and anything about a good adventure!

Favorite Books: Harry Potter, Lord of the Rings, Hitchhiker’s Guide to the Galaxy, and anything about a good adventure!

Fun Facts: Ms. King loves Swing dancing and used to teach Swing classes at UCLA! She likes sharing, and trying new things is one of her favorite activities.

email: [email protected]

Music Classroom Blog


Physical Education Teacher: Kevin Killacky

PE Kevin

Education: Mr. Killacky was born and raised in Bonita and Chula Vista, graduating from Bonita Vista High School before attending the University of California at Santa Cruz where he earned his BA in American Studies. He then moved on to San Diego State University for his teaching credential. He is also the proud dad of three!

Teaching Experience: Most recently, Mr. Killacky worked at the elementary level teaching PE across the bay in Coronado, but has taught middle and high school PE as well in the Sweetwater High School District.

Hobbies: Mr. Killacky loves to be outdoors, spending time running local trails, swimming, or riding his bike. In fact, an ongoing project of his involves the construction of an outdoor BMX track in his backyard. He also plays a bit of indoor soccer on a team with his family.

Fun Facts: When indoors, Mr. Killacky enjoy classic films and reading just about anything by John Steinbeck. Although, sometimes he reads outside, too.

email: [email protected]

Physical Education Classroom Blog


Office Manager: Nathalie Hirsch


Education: BA,Psychology from National University

AS, Paralegal Studies, Office Administration

Experience: Ms. Hirsch has plenty of office experience. Her background has been as a legal administrative assistant for several years for some of the top attorneys in their field. She has also volunteered as an academic advisor at the community college level.

Hobbies: She loves to cook, listen to live music and spend time with her 3 girls and partner of 15 years.

Favorite Books/Things to Read: Cookbooks! She also loves The Mists of Avalon series by Marion Zimmer Bradley and Le Morte D’Arthur by Sir Thomas Malory, she has a thing for Arthurian legend.

Fun Facts: She owns over 100 cookbooks (easily, might even be pushing 200) and studied dance since she was 2 all the way through college and even taught ballroom. Her favorite types of dance are the Argentine Tango and Tahitian dances. She is keeping her fingers crossed that her girls will want to take dance lessons!

email: [email protected]


Day Custodian: Aracely Hobbs


Would like to learn photography and really wants to get into scrap-booking, but her focus is her kids.

Favorite Book:
Chicken Soup for the Soul.

Fun Fact:
Former military family for 14 years. Mrs. Hobbs has a 19 year-old daughter and a 15 year-old son. 99% of her time is dedicated to her children.

email: [email protected]


Custodian: Miguel Angel Pena


Education: Some college.

Hobbies: Watching football, trying to grow his business. His favorite time is spending time with his daughter and his dog.

Experience: Security and janitorial management for 9 years. Mr. Pena is very excited to be at OTA.

Fun Facts: Mr. Pena’s daughter is a female version of him. She looks just like Mr. Pena!


Core Knowledge Advisor & StandUp For Kids Coordinator: Bob Hamm


Education: B.S. Education, M.Ed. Texas Tech University

Experience: 8th grade history teacher-University Junior High School, Waco, Texas
Principal, St. Louis Catholic School, Waco, Texas – 1980-1989
Principal, Sacred Heart Academy, San Diego, CA – 1989-2009
Sacred Heart Academy was the first Core Knowledge school in the state of CA.

Hobbies: Raising orchids, and hanging out at the pool.

Favorite Authors: E.D. Hirsch, Jr, James Patterson, John GrishamSchool

email: [email protected]


Education Specialist: Kirsten Ramirez

Education: Ms.  Ramirez Graduated from Cal State East Bay with a Bachelors Degree in US History.  She went on to receive her Masters in Special Education and Teaching Credential at Loyola Marymount University.

Teaching Experience: Ms. Ramirez started her teaching career as a Special Day Class Teacher for High School in Oakland California.  She later switched to teaching Special Day Class/ Inclusion in a 6-8 classroom in Oakland before finally coming here to teach at OTA!

Hobbies: Ms Ramirez enjoys playing with her Australian Shepherd, watching movies, reading, swimming, and yoga. 

Favorite Books/Things to Read: Slade House by David Mitchell, El Deafo by Cece Bell, Wonder by RJ Palacio

Fun Facts: Ms Ramirez just recently moved back to the San Diego Area from the Bay area. While she will always remain a Chargers and a Padres Fan, she is now a die hard Warriors fan.

email: [email protected]


Speech Language Pathologist: Jessica Reed

Education: Ms. Reed graduated from Central Michigan University with a B.A.A. in Communication Disorders. She then moved across the country and received her M.A. in Speech-Language Pathology from San Diego State University.

Experience: After graduating from SDSU, Ms. Reed worked as an SLP in Chula Vista for three years and then in National City for another three years. In both school districts, she worked with children from preschool to 6th grade. In addition to her school experience, Ms. Reed provides private speech services to children from toddlers to teenagers

Hobbies: When not working with children, Ms. Reed enjoys traveling, hiking, doing puzzles, reading, and playing board games.

Books: The Harry Potter series, Rebecca by Daphne Du Maurier, The Goldfinch by Donna Tartt, The Giver by Lois Lowry, and most mystery/thrillers (particularly Stephen King and Angela Marsons).

Fun Facts: Ms. Reed loves to travel to other countries! Her favorite place she’s visited is Queenstown, New Zealand, which she traveled to in 2015. Her craziest travel experience happened in 2009, when she (along with 49 other travelers) were quarantined to their hotel in Germany for three days due to a swine flu outbreak.

email: [email protected]


Special Education Instructional Aide: Kathleen Fontimayor


IMG_7353Education: Currently undergrad student at South Western College majoring in Education.

Teaching Experience: Kathleen has lived in San Diego all her life. This is her first year working at OTA. She has spent the last 4 years working in different after school programs as an activity leader. She has also worked in preschools as a teacher’s aide.

Hobbies: Ms. Kat loves to take trips to Disneyland. She also enjoys dancing, arts & crafts and spending time with her one-year-old dog.

Favorite Book: The Things We Keep Written by Sally Hepworth, A Child Called It Written by Dave Pelzer & The Hunger Games Series

Fun Fact: Ms. Kat owns a few rare pair of shoes. She also loves to Jet ski!

email: [email protected]


Principal: Jon Centofranchi (and family)

Education: Mr. Centofranchi earned his Bachelor’s Degree and teaching credential from California Polytechnic University, Pomona. He later earned his Master’s Degree in Educational Administration from National University in Vista.

Teaching Experience: Mr. Centofranchi taught physical education, science, electives, ASB (student leadership), and Opportunity School before becoming an administrator. For the last 14 years, he has been the principal of both elementary and middle schools. He has also coached basketball, football, soccer, and track, as well as led a running club and surfing club.

Hobbies: Mr. Centofranchi enjoys backpacking, surfing, running, and biking.

Favorite Books: Rain of Gold, by Victor Villaseñor; Profiles in Courage, by John F. Kennedy; and What Do You Do With an Idea?, by Kobi Yamada.

Favorite Subject in School: History and Science.

Fun Facts: In addition to having completed 13 marathons and 6 ultra-marathons, Mr. C ran 50 miles on his 50th birthday!

email: [email protected]