Experience of the world of work is important for several reasons. It can definitely strengthen an application for a college or university course, firstly because it can show that you have got related experience to the course applied for. This would demonstrate that you have a good understanding of how the course content relates to the working world. Regardless of whether the experience is related to the course or not, some of the skills you gain from the experience can make you a better student. For instance being able to demonstrate that you are organised, motivated and good at communicating will all be very helpful in enabling you to succeed as a student on any course.
Work experience is also a very good way to develop skills that future employers will want to see, and demonstrate that you are 'a good match'. Experience combined with qualifications is what employers regularly want to see from applicants. These skills can be technical ones that are specific to a job role or vocational sector or transferrable ones which are useful across all sectors. Transferrable ones include ones like communication skills, problem solving, team work and showing initiative. Having examples of these skills will help you to maximise your chances of finding work in the future that you are interested in.
Another benefit is that doing work experience will give you some good contacts and references to use in the future to find work opportunities!
These following websites might be of use: