8.9" kindle fire HD vs. ipad 4 vs. ipad mini

I have been wanting an ipad for homeschool purposes, but because I don’t need one haven’t saved up for one.  I have just enough money to buy the kindle fire HD with the 8.9″ screen or the ipad mini.   I know Doug would recommend the ipad 😉 .  I purchased the regular kindle fire last year and think it is worth the money for the purposes I use it for (mainly compact size to fit in a purse and take anywhere, reading, and quick access to the internet when I want to look something up quickly).  But for homeschool, I want a bigger crisper screen to look up things like artist prints, watch educational youtube videos, better speakers, read pdf document downloads like the MEP lesson plans with less eye strain, enjoy illustrations from books on a larger screen, typing emails is a pain for me on the regular kindle (I don’t even text, gasp!), and such.  I know I would LOVE an ipad 4, but possibly not for $200+ more.  I’m not high tech and don’t care to have all the latest and greatest gadgets on the market.  However, I do want the best value and quality for each dollar. My only hesisitation to the ipad mini is that the screen size is smaller than the 8.9″ kindle.  To get the ipad 4, I would have to wait quite awhile.  Any thoughts or experiences?