- Title: 반올림1 / Banolrim 1
- Also known as: Sharp / Rounding Off 1 / Sharp 1
- Genre: High school romance / Comedy
- Episodes: 64
- Broadcast network: KBS2
- Broadcast period: 2003-Nov-29 to 2005-Feb-27
- Air time: Sunday 8:00 AM
- Related TV shows: Sharp 2, Sharp 3
Lee Ok Rim is 15 years old. She likes imaging and has bright personality. She is very frank about her feelings. She also knows that she is pretty and uses that. At home she is the second child who is placed between an older sister who studies well and a twin younger brother. Ok-Rim has a boyfriend Yoo Ah In who is studying painting in high school. Ok Rim also has a long time male friend named Jangwook. Between Yu Ah In and Jangwook she is not sure about her feelings.
Jangwook is stubborn, shy, but cool. Since moving next door to Ok Rim, they have become best friends and knows all of her secrets. Like boys around his age, Jang-Wook likes soccer and gets into mischief. He is also warm and becasue of that Jangwook is popular among his peers.
Yoo Ah In is a sophomore in high school studying painting and Ok-Rim's boyfriend. He makes jokes and is sociable, but does not talk about what is really on his mind. Ah In started paining late, but with intelligence and persistence he has won the several contests. Ah In is mature and smarter than his girl friend Ok-Rim, so he controls their relationship. But, there is rival Jangwook and Ah In tries his best to hold onto Ok Rim's affections.
- Go Ah Ra as Lee Ok Rim
- Park Hoon Jung as Lee Ha Rim (brother)
- Kang Suk Woo as Lee Sang Heum (father)
- Lee Eung Kyung as Kim Sung Hee (mother)
- Suh Hyun Suk as Jang Wook
- Lee Eun Sung as Seo Jung Min
- Kim Si Hoo as Lee Soon Shin
- Yoo Ah In as Yoo Ah In
- Kim Jung Min as Park Se Ri
- Oh Yeon Seo as Lee Ye Rim
- Kwak Ji Min as Kang Dong Hee
- Choo Ja Hyun as Na Re Yi
- Kim Ha Kyoon as Kim Jung Sik
- Hyun Jung Eun as Lee Yoon Jung
- Lee Min Ho as art academy student
- Oh Soo Min as a student teacher (cameo)
- Heo Yi Jae
- Actress Lee Eun Song is listed in the cast under her previous stage name "Eun Sung".
- Producer: Jang Sung Hwan
- Director: Choi Se Kyung, Kim Jung Hwan, Park Ki Hyun, Kim Jin Hwan
- Screenwriter: Hong Jin Ah, Kwon Ki Kyung, Hong Ja Ram