Because the cost of the test strips are the major & regular outlay, many people who have to self fund their testing opt for the SD Code Free meter as this has by far the cheapest strips. Available from Amazon, eBay, and the suppliers own site:
http://homehealth-uk.com/
If you definitely want nice and discreet and wouldn't mind the high cost then take a look at Abbot's Freestyle Libre (
http://www.freestylelibre.co.uk/products.html). It's a small continuous glucose monitoring sensor you wear on your arm, and swipe with a reader when you need to actually see a graph of recent levels. No finger pricking required, and swiping could probably look as if you were just rubbing your arm. Sensors last a fortnight at a cost of just under £60(!!) each, and the one off cost for the reader is the same.
If you are diagnosed as diabetic you can claim VAT relief on testing goodies.
There are some teachers on the forum, and I know that one of them,
@Scandichic, would test in class and as far as I can remember she just told the children what she was doing and why - so a little bit of extra education for them.
Robbity
PS
@urbanracer beat me to it, but as you see great minds think alike.