Bests & Worsts Reviews from Amazon

National Geographic Dual Microscope has surprisingly clear lens for an inexpensive microscope. The microscope has 10x and 25x lens that are easy to exchange. You simply pull to remove the lens and the next lens slides in. The distance between the two heads is adjustable, but this does not have a Diopter adjustment. You do have the Coarse Focus knob to adjust the distance from the specimen you're viewing. You have two different light sources, one from above your field of view and one below the stage that shines through the condenser lens (glass circular piece). The condenser lens comes out easily, so make sure to be careful when unboxing. Depending on what you are viewing the light source from below may still be too bright to see details. We found that if you take a small piece of wax paper and place under the glass piece it diffuses the light more and makes the specimen easier to see. There are many slides that come in a plastic case and most are already setup for viewing. (Examples: onion skin, fungi, earthworm cross section, etc.) The earthworm slide is one I would recommend diffusing more with the wax paper to see the individual layers of intestine and epidermis. This set also comes with a vile of Brine Shrimp eggs and a hatchery. The instructions to hatch the eggs are in the instruction manual. It's quite simple to make the saltwater using bottled water and salt without iodine. The eggs are supposed to hatch 24-48hrs later, but we were unable to see any hatch after waiting four full days. After research, there are many factors that could cause the eggs to not hatch, such as water was too cold, too many eggs, etc. You are instructed to place the hatchery in a window sill and it has been cold outside. With the shallow water for the eggs I fear the water may have gotten too cold. I will start the hatching process over very soon. The microscope is battery-operated and requires 2 AA batteries that are not included. Otherwise, this is a near complete starter kit for a teenager who is interested in science. I have a 7 and 6 yr old that enjoy looking through the microscope with our help. They love to find things when outside and bring in to get a closer look! Thanks for watching!