opening partitions with uSD boot

i have a 2gig version BBB. i finally figured out how to flash the dhamn thing. first i downloaded the latest version of debian 4gig uSD bootable. It worked, but when i used the df -h command to see how much storage space i had to work with, i was only allocated the 4 gigs on a 16gig uSD card. because of this i switched to the 2gig emmc version of debian so that i use my uSD for storage. i dont want to do this. i would rather have the latest version of debian using the uSD to boot, but still get all the use out of my uSD card. my raspberry pi works this way. i am able to boot Raspian from the uSD and use the remaining space on the sd card for storage. how do i do this with my BBB?

If you run on a uSD card, be aware that the file system as downloaded will be restricted to the size of the intended eMMC, but you can expand the file system to the full size of the card, with the encantation:

cd /opt/scripts/tools/
git pull
sudo ./grow_partition.sh
sudo reboot