Recently I try a freescale board the freedom KL25Z and I work with two realy different system to play with this board. I give you some information to use the best for you.
engine - 48Mhz, 128kb flash, 16kb sram, usb otg, 80LQF arm cortex-M0+
body - capacitive touch (slider), mma8451q accelerometre, tricolor led, reset button, 2 usb, rtc battery-ready(just need battery holder and soldering), 64 pin I/O with arduino R3 compatible
Coocox have lots of interesting stuff. Use the board like a fat ide, a RTOS os(coOS) and Coocox flash programing soft and a library. I try the IDE the software have a lots of add. When you want to download you need to registre and login before but it's free. After you need to intall gcc compiler because is not integrated. After you need to update your board it's easy just download the firmware copy and paste on the board reset and your ready to program it.
The link for all information to start with a feescale board and coocox http://www.coocox.org/downloadfile/CoIDE/How_to_use_OpenSDA.pdf
All the register, download, install and update is little bit longer than arduino ide. But after all you have a powerfull and totaly free IDE you can use with lots of microcontroler atmel, freescale, nxp, st, ti, etc.
The all in one website:
MBED is a free and open development tools website. You need to registre, log and update before everything. Little bug if your are on linux or mac you need a computer with windows to make the first update.
The link for start with your board it's here https://mbed.org/platforms/KL25Z/ and when your go to the online compiler you have all information about the compiler. You can just import the code you whant in you compiler and compile with everything you can go on the web site I have samsung tab 10.1 and I can compile and download the program on the board without mod. If the code you whant to use on the website are not compile for the kl25z board you need to make a little mod before you compile and change the library for the latest update(but lots of code have change now).
Now choice and code