Declining Admission Too Soon?

I have earned my Associate in the Arts in Teaching degree, and am taking one class this summer to finish completing the general undergraduate requirements for one of the universities that I have applied to.

I have been formally accepted to the University of Washington at Bothell, accepted into two of the programs that I applied to at Western Washington at Bellingham, but am waiting for Western Washington at Everett’s decision. Everett would be my first choice due to their academic program for my major and the distance from where I live. They seemed interested in me, but an official decision will not be made for at least another week-week and half.

UWB requires a decision on my part made before the 26th of this month. I like their program description, thus far, even through it would take me a different route towards teaching (since they do not have an Education BA program). I am afraid that if I decline admission now, and do not get accepted to the Everett program, then I will be risking having no school to attend in the fall. If I give them notice later than sooner, then I will be being inconsiderate towards the school and towards the students on the waiting list.

What should I do?