I think the site looks great. There could be a major issue with the whole project though.
Data Protection and storage of information being held on school children on external servers. Even if it was installed on say a school's own mysql I cannot see any school allowing external access to their servers. I am talking from a UK point of view. This type of system would raise many issues.
For this to work in the UK, the sites owners and all employees of the site's owner would have to pass through annual disclosure checks by Police and Social Services.
The laws could be different in other countries and I genuinely wish you luck with it.
Just to let you know that I know what I am talking about here read on.
I own a company, we hold financial details on customers. We have a data protection license issued by the Information Commissioner's Office. We have a mysql database that contains the names, phone numbers addresses of every customer. We grant access only to other companies that hold data protection registration. Even then the other companies (mainly car dealrs) can only then access our customers details if we have ordered the car from a dealer. Each dealer we grant access to can only view the customers relevant to them, so say we order a citroen for a customer, then the citroen dealer will only see the list of cars/vans that we have ordered from them. All other customer information is kept secure, the dealers can only access fields such as customers name, number, vehicle ordered. No financial data is disclosed to the dealer.