Reddit mentions of Loupe Set - Dual 10x+20x, 10x, 30x, 3 Pc

SE - Loupe Set - Dual 10x+20x, 10x, 30x, 3 Pc - MJ361830C https://www.amazon.com/dp/B001C9LG60/ref=cm_sw_r_awd_7l-IwbFE08DGC

I use one of the 30x ones from this set, you could probably find one individually for $6 or so. 30x vs. 40x or 60x may not matter much for you. They're really common and there's nothing particularly special about that set. I already had them because they're also really useful for working with tiny electronics. :) It works to hold it to the lens on my phone, too.

When I started growing cannabis I tried getting one of the adjustable hand microscopes, but I found it much harder to use that the loupes I already had unless I cut buds off the plant and held them flat.

i can easily see the blue line with one of these, which fit on a keychain

http://www.amazon.com/SE-Loupe-Set-Dual-10x/dp/B001C9LG60/ref=pd_sim_op_3?ie=UTF8&refRID=0P8J0B8YSF68S4GM553V

loupes also effective in seeing the blue line in a stack of 100 or so cards very quickly

http://www.reddit.com/r/askscience/comments/e1sa0/my_kids_asked_santa_for_a_microscope_for/ Some not bad advice in that thread. Let me second a stereo-microscope. The stereomicroscope in my lab is easily my favorite to play with. I'd start by reading this

I think something like this or something like this which are, as far as I can tell, modified dermatologist scopes, might be good for a 5th grader. (Reviews are pretty good indicators on this, though don't trust zoom numbers most zoom 20-30x and the rest is all digital.) I spent a summer volunteering at a place with something like these, they are fun. Also if you want something that doesn't take pictures but is a pretty neat field scope you should check out, this, this, or this (note, jeweler loupes do not have lights built in). If you want something kind of medium range, most sites recommend Celestron scopes as pretty good. If you really want a compound microscope (and you know how to operate a microscope, I can't emphasize this enough, otherwise it will not work!) this is recommended by the microscope buying guide. (Also as someone else said, you will run out of stuff to look at pretty fast with a compound scope.) Though that site has a number of nice compound microscopes.