If possible she should try to find out the name of the person who she is writing to.
Dear xxxxx,
I like many other young people going onto further full time education in the autumn am looking for seasonal work in my home/new collage area.
Other than my school work placement and babysitting duties, which I have gone into more detail on my accompanying CV, I have no direct experience of working within/in the xxxsockxxx trade. However from my CV you will see that I am able to learn new duties quickly and am capable of working both within a team and on my own initiative. BIG YOURSELF UP A BIT BUT DON'T GO OVER THE TOP. Punctual, customer service etc.
If you are looking to place seasonal workers with possibly a view to working on a weekend or casual basis after this I would be grateful if you would consider my application favourably.
I look forward to hearing from you soon.
Yours etc