A few comments about District DNA and the Web.
It is not web based. Its database (firebird – robust – powerful – free) sits protected inside your firewall. I have yet to see a web based system that adequately address the security problems of having your mission critical data outside your firewall (even if it inside, a hole exists, it has to). Is it possible to setup a secure system? Probably. See e-weeks open hack competition, where experts secure an exposed database.
After reading the e-week competition, ask yourself if your school or any school has or can afford that level of expertise, never mind some very expensive databases. I have spent over 20 years in school data processing and even in school districts with 100+ schools, I have never seen it.
What does a web interface do for a developer? It gives him less interface tools to work with. Anything a web interface can do (UI speaking) a regular GUI can, but the reverse is not true. It adds complexity because it must maintain a stateless connection and complexity means bugs. The only positive advantage is that it is cross platform (at least potentially). Heck I use Mozzilla, but I have to keep IE around because some web sites require it.
What does it do for you the school? It requires no client software installation other than the presumed already there browser, saving you maybe 2 minutes per workstation. It is slower and likely has a less efficient UI (User Interface). I ignores the processing power of your workstation, making the server do all the work (seems like the old time sharing days) requiring a more powerful (read expensive) server. It allows you to work from anywhere (of course it also gives hackers their shot from anywhere). I have always regarded the programs I write as tools to allow you to work less, not work 24 hours a day from anywhere.
Oh, one thing I forgot the web allows your parents to login securely and check on there son/daughter. Boy that sounds like a good idea. Forget for a moment the security problems (they get to see someone else son/daughter, or worse yet the password gets past around the student body), it requires the parent to learn an interface and to take the initiative to login and check out things.
In my experience as a teacher (not to mention that I wrote such an interface for one school) the parents who most need to do this are the parents lest likely to. The approach I took in District DNA is to e-mail the parents notifications. You son is absent today etc. The parents can get the information at work etc., by doing what they normally do, check their e-mail. No interface to learn, no special initiative on there part. That approach of course is more work on your part. You need to maintain the e-mail address and what the parents want to know. Of course it also gives you more information; you know what information the parent has received. What a nice bit of information for a parent conference.