No one is ever too old, I worked with a lady who must have been in late 50s in my last job, she was a qualified teacher returning to work. The only thing that I found a hinderance was her attitude to be honest.
At Uni in the UK we had plenty of mature students and they integrated really well ... we enjoyed their company too, it was nice having older people with a mature outlook to life and studying ...we had to complete our assignments before they allowed us to run to the pub or out clubbing
I am 35 and just completing my Diploma, though doing through Correspondence.
In my opinion if someone is a friendly person it does not matter what age they are. Like Sharlene said your life experiences can make a big contribution to the class. You will learn from the younger ones and they will learn from you.
Good Luck with the studies, I am sure you will have a great time and if you need help everyone on here is super helpful