List Query for Schools

I would like to pull a list in List Manager of all constituents having any school recorded on their account under the Research Tab.

I need some help with the manual edit of the query code.  Is there a way to do this without listing the numbers of all 1,500+ schools?

Select Distinct a.customer_no
 From t_customer a (NOLOCK)
JOIN vxs_cust_school e (NOLOCK) ON a.customer_no = e.customer_no
 Where  IsNull(a.inactive, 1) = 1
 AND e.school in  (2,3,4,5,6,7,8,9,13,14,15,16,17,18,20,21,22,23,1458,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74)

Thank you!

Chuck Buchanan

92nd Street Y