I used to study spanish at the Shanghai International Studies University. At that time it was around 500 RMB/semester with classes 2 hours 2x/week.

However, if you don't speak Chinese, it's a bit difficult, because the student books are in Chinese and Spanish. 

Do you need specifically the classes in a institute or university? because I´m  a spanish teacher but  are personalized classes.

You can check out some of the universities in shanghai and take spanish as your foreign language class. Another way to learn spanish if your not interested in attending a school is to find a one on one tutor. I've taken Spanish as my foreign language and I still have some of the materials I used before. If you do learn spanish you would want to use a combination of listening reading and writing. You could check out some instructional videos or dialogue on the internet and for the reading and writing practice your tongue roll and you pronunciation.

I can teach you Spanish. I'm not working right now, so I am free most of the time. I'm Mexican so my native language is Spanish.

New Oriental had advertisement on echinacities for Spanish teacher few weeks ago. 

You should try Shanghai New Oriental for info about Spanish classes.

¡Hola! My name's Patricia. I'm Spanish, from Barcelona, and I live in Shanghai. I've the certificate of TSFL, Teaching Spanish as a Foreign Language, from University of Barcelona, International House Language School and Instituto Cervantes. I have more than 9 years of experience teaching adults and children, all levels, groups and private lessons. I'm also a Dele Examinator from Instituto Cervantes. DELE it's the official certificate for the Spanish language. You can contact me by email patriciammunoz@hotmail.com or phone 18217595658.

There was a Spaniard on this forum, few days ago who was looking for a teaching job in Shanghai as a Spanish teacher. Maybe that's his opportunity. 

Hola, I'm Patricia again. I have a spanish school in Shanghai near Shanghai Stadium station.
Study Spanish in Shanghai. Spanish courses in group and private lessons.
All Spanish levels: A1, A2, B1, B2, C1 and C2. We also offer DELE preparation courses.
Courses for children, youth and adults. Also courses for official tests for kids (DELE Escolar).
Courses and guidance to study in Spanish universities. Processing of documents.
All our teachers are native and has TSFL (Teaching English as a Foreign Language) certificate.
Group classes are 4-9 students (small groups).
Private Spanish classes can be in our school, in your office or in your home, at the time you wish.
Our school is close to the Shanghai Stadium subway station.

You can contact us by email: directorpatricia@spanishshanghai.com, WeChat mon84106 (chinese and spanish) or liuxiaxia83 (spanish and english) , or telephone: 180-1759-6015 (Chinese and Spanish), 136-6179-4197 (Spanish and English).

We also offer Spanish-Chinese translation.
And courses of French, Italian, English, Catalan, Chinese, Shanghainese, specific business and marketing language courses, painting for children and adults, etc.

********

帕特丽夏西班牙语和绘画学校在上海开班了。西班牙语课程包括小班制和VIP  。课程包含各个等级的西班牙语：A1,A2,B1,B2,C1,C2。我们也开设西班牙语针对DELE考试的预习班。

所有的课程都开设幼儿，少年和成人班，以及针对官方考试的课程。开设针对将要去西班牙留学的学员的课程，为学员提供留学方面的咨询和办理留学手续。我们所有的老师都是母语为西班牙语的老师，都拥有TSFL（教授外国人西班牙证书）的老师小班制课程为4-9人VIP课程为您量身打造，可以选择在我们的学校，在您的办公室或者在您的家里，上课时候也由您来订。我们的学校坐落在上海八万人体育场边上。您可以由以下方式联系我们：directorpatricia@spanishshanghai.com， 微信：mon84106, 电话：18017596015刘老师（中文和西班牙语咨询）13661794197（西班牙语和英语咨询） 除了西班牙语外，我们学校还提供以下课程和服务：中西翻译，法国语课程，意大利语课程英语课程，加泰罗尼亚语课程，汉语课程，上海话课程（沪语），书法课程，和所有绘画课程。

If you are looking for a Spanish tutor - check out http://www.soufudao.com

Lots of tutors and you can message them for free:)