Good calculator

i am teaching a group of middle school kids math as a side job and we are going to cover a matrix section.

My question is: does anyone know a good scientific that can solve matrix problems.....under $40.

I was looking online and it looks like a casio Fx-991es can do a 3 by 3 matrix but its not readily available.

The more available Casio FX-115 es can also do a matrix problem but it seems like it can only do a 2 by 2.......if that is the case then its not worth getting one because these kids should be able to do a 2 by 2 by hand with paper and pencil.

I dont want them to get into graphing Ti series calculators because the scientific is a lot cheaper and legal to use in exams where some exams wont allow the use of a graphing.

either one can do the quadratic equation with one button setup which is nice and easier than a Ti.

I am just trying to save them some time .....knowing the Gauss-jordan method or cramers rule is nice but holy cow it takes so long during an exam.

i know theres a bunch of automotive math gurus here