BROOKLYN - Figuring out the individual needs of every student in Brooklyn and the rest of the city may seem daunting, but the Department of Education is taking a stab at it.The department is developing a computer system that can track a student's performance and progress during the course of the school year. The Achievement Reporting and Innovation System will be the first of its kind and allow teachers to improve and individualize instruction based on a student's needs.The system is being developed by IBM. The five-year contract with the computer giant will cost the city $80 million. Teachers' Union President Randi Weingarten claims the money should go to buying supplies and lowering class sizes. Mayor Bloomberg (R-NYC) insists the city will spare no expense to provide each child with a quality education.