Lexia, Read Naturally, Hyperstudio Opensource Alternatives

Hi Everybody, I'm working on convincing my admin staff to try to convert some of the school over to open source software so we can take the money that we are wasting paying for software and put it into hardware. The issue that I'm running into is that I'm not having much luck finding open source alternatives to some of the software that we use like Lexia, Read Naturally, Hyperstudio. Has anybody had any luck finding alternatives to these programs? What are some of the more useful applications that you have started using in your school? Thanks for the ideas and the help!

- Seth