We've got WUSTL people on staff, and I'm sold on the caliber of its grads, but direct-to-school recruiting has been a dead-end for us at other schools.
As a recent (Spring 2012) graduate of the WUSTL School of Engineering, I would highly recommend that you contact the Career Center[0] for opportunities to participate in career fairs and register as an employer on CareerLink[1], WUSTL's career website. The Career Center pushes CareerLink hard with students, so if you post jobs on there, there's a good chance you'll get some bites.
I attended a career fair just this spring, and it was packed with students - there were sometimes lines up to 10 people deep just to talk with industry representatives. Don't give up so quickly on direct-to-school recruiting.
You should also look into offering summer internships for current students. IIRC, WUSTL will match whatever you pay interns, making it less of a financial burden for you, while still making it worth the student's while. This is another way to grow your "reputation" on campus.
Finally, the students may find it easier to connect with an alum - get your WUSTL grads involved in the recruiting process.
0: http://careercenter.wustl.edu/
1: http://careercenter.wustl.edu/tools/careerlink/Pages/default...
If that's the case, you really need a way to reach those top tier students. Do you have any positions that would seem intellectually rigorous and interesting? If so, I'd find a professor with relevant interests and shoot them an email saying you're looking for a top-tier intern and that you have some really cool problems for them to work on. Some professors are obviously more industry-friendly than others, but in my experience, there are at least a few who would probably be willing to help.
Another option would be to host an event at Wash U. I'm not entirely sure how this works from a logistical standpoint, but it's common at Wash U for companies to reserve rooms for different types of recruiting events. Some companies might host hack-a-thons. Some might do giveaways. EA did a presentation on how video games get made. Those events generally get a lot more attention from the top tier students than the career fair booths, and professors often promote them at the end of class. I'd guess that contacting the Career Center would be your first step if you want to set something like that up.
Hope that helps.
My favorite OR classes are when we come in and reverse engineer a popular internet service (e.g. starting with Google Maps, and spending a week going from integer programming to linear programming to heuristics as we iterate through better methods).
We contacted the University ACM chapter and threw them a party -- pizza, wings, XBox, music, etc. Told them to bring resumes and had enough of our engineers around to answer questions. It was fun and we got our hire.