volunteer job at Almaty stuttering foundation, Commonapp short essay

Prompt:Elaborate one of your activities extracurricular,personal activities or work experience.(150 words)

Please give some feedback to this essay. I also think that there are plenty of grammar mistakes.)

During 11th grade I devoted more than 15 hours a week to volunteer job at Almaty stuttering foundation. During financial crisis foundation experienced serious problems, because many companies refuted to fund our organization. I could not abandon it, because I saw many children who needed help. With my classmates I started to new campaign of fundraising. Everyone contributed a lot to this projects. I was responsible for the website and design of presentations. Those who were good at statistics calculated predicted number of stuttering children in Almaty based on undertaken surveys. Some of my friends wrote articles to some local papers. At the end I visited more than 50 firms with financial support request. After long discussions only 4 of them agreed to it. However it was enough to cover organization's basic costs. It was a unique experience: before this project I was unaware of my leadership and interpersonal skills.(149 words)

Thank you in advance

Grammatical errors:
"During the financial crisis the foundation..."
".. started a new fund raising campaign."
"everyone contributed a lot to this project."- we want to know what you did and not everyone else so remove this.