acl reconstruction?

Acl reconstruction needed or not?
I am 34 and completely tore my acl about 3 and a 1/2 weeks ago and was initially told that i would need to have it reconstructed. However today the consultant has said give it 3 months and if strong enough then they may just leave it. My concern is that i work as a sports teacher and possibly have another 30 -34 years to work in this field. Obviously my role involves a lot of high impact work and most common sports are taught which require sudden changes in direction. I also still take part in sports including soccer and badminton. Do you think my knee will cope in future without reconstruction as i am quite worried about it in relation to my job and sporting lifestyle.

Also what are the pros and cons of having or not having the reconstruction done. Thanks in advance for your help!