Hi,
A great resource for researching local school districts is SchoolFinder:
http://www.education.com/schoolfinder
I did a quick search using the zip code 91504, and it does appear that Burbank Unified School District is the correct answer. Here is their page in SchoolFinder, which has their phone number so you can call to confirm:
http://www.education.com/schoolfinder/us/california/district/burbank-unified-school-district/
The district can also tell you which local school(s) within their district that your children would be able to attend (some districts assign residential zones to particular schools).
Thanks for asking!