Living next to a school, any school is always an issue. How close and what it over looks at the school are important also. Traffic at pick up and drop off is a big deal. Some wont mind but most will which ultimately decreases demand for the home and hence value. In a great sellers market (like now and the peak bubble years) it doesnt make much of a difference but if buyers have other choices they will go elsewhere.
A smart seller will sell such a home in Summer when kids are out of school and you cant see the real impact. If I was going to buy one next to a school I would want to do it during the school year to see the real impact as the mind can tend to minimize what the impact would be. If I was your agent I would try to talk you out of it. I would think that would be worth a discount of 10% perhaps more. Personally that isnt something I would put up with at any price but everyone feels differently.