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Ask Slashdot: Advice On Child-Friendly Microscopes?
OceanMan7 writes "My 7-year-old son is getting very interested in microscopic things — from bacteria to parameciums (paramecia?) Not being a biologist, I would appreciate advice on what type of microscope to get. I'd be operating it and he viewing with supervision. I'd like something better than a toy and plan to buy it used, if possible. Extra points if it's stereo and also allows me to view opaque objects at low magnification."
I'd suggest a $100 or so USB microscope. You can use it to look at opaque objects, and you can have the picture on your computer screen. That would be a big help when trying to point out what the kid is seeing.
The ant burning ones are called magnifying glasses.
Anyway, Stereo microscopes generally have less magnification, forget viewing bacteria with these, if you want to study the surface structure of wood or insect eyes, then sure, get a stero.
Otherwise, get a classic 'university-grade' turret microscope with one oil immersion objective.
Consider however that you may need dyes to stain your samples or you won't see all that much unless you get a phase contrast microscope. Consider also that you need thin translucent slices if you want to view tissues. If you just want to explore your saliva or the fauna in forest ponds, then you don't need as much.
Also, there's no microscopic pornography or ultraviolence so I'm pretty sure you can let him operate it all on his own, just make sure he doesn't oil up the normal objectives or store the slides in his mouth.
One of the webcam models works well with kids because its cheap and displays on a big monitor, so you can look at stuff together. Some of the better ones show up as if they're normal webcams so you can have some weird internet chats with friends and family (G+ hangouts?) "Hey grandma, look at this giant ant leg" etc.
The other alternative is ebay. A kid is much better off with a worn out but "real" microscope that's probably cheaper than a hunk of Chinese plastic anyway. Some people are weirdly proud of being completely mechanically inept... they are a bad target market for used scopes.
Another alternative is new chinese steel. At a place like lwscientific.com you can spend about the cost of a good video card and get a new, "real" student grade scope that'll last forever.
Absolute worst case scenario is a cheap hunk of Chinese plastic with "900x" magnification listed on the box right next to ridiculous artists interpretations and electron microscope images. Oddly enough the marketing is just about as misleading and poor for other optical devices like telescopes.
You mentioned "parameciums". Its easy to find samples of plain ole dirt, grass leaves, etc. If you want "real prepared slides of weird or interesting organisms", go somewhere like carolina.com, "life sciences" "microscope slides". Note that a good prepared, preserved, stained slide is gonna be like $5 per slide. There are somewhat dodgier suppliers at a somewhat lower cost, but not as cheap as you'd think. On the other hand, my kids find it infinitely more interesting to run around in the yard, pick something up off the ground, and look at it under the 'scope.
Maybe the best place to start a kid with microscopes is a hand held magnifying glass. Much as you're supposed to "do astronomy" by starting with eyes first, then binocs, then get a scope...
I have no financial connection with any of the above other than spending money on stuff like this.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Get a toy one
At 7, it will be great
Get preferabily one with >= 50x mag, so you can see cells, etc
Later you can think of a better one
I really don't remember how old I was when I got my first (toy) one, but it was a built-it-yourself kit
Then I got one that was 100x-300x-600x (which was 'more real') and it was lots of fun
how long until
Hear hear. I had one of the old Intel QX microscopes and loved it. Any USB microscope will let a child see things on a nice big screen and many of them, like the QX3, are ruggedized for kids. It's pricey, though, compared to other desktop USB microscopes of which there are many, as other posters are mentioning (search Amazon), but the design should make it worthwhile. I haven't used the software in a while; it was a bit buggy last time I played with it, but hopefully it's improved.
If you really want eyepieces, there are some that do double duty -- Celestron makes entry-level microscopes that have replaceable eyepieces (so you can use it like a traditional microscope or mount a camera on it, but not both at the same time), or ones with LCD screens directly built in instead of traditional viewfinders.
As you near the $250 barrier you can get scopes that start to do double-duty, and your options increase. These are more lab-ready and may need more oversight for a 7-year-old, and frankly I find them harder to use for kids, but the ability to look through an eyepiece to set up and focus a shot and then discover the results on a computer make for good two-person work in parent-child fashion.
I'm not sure of your budget or whether you are looking at this for yourself or your son, but a trinocular scope allows human binary focus on the subject/target as well as a digital imaging output that can be displayed on a dedicated Workstation or PC. These images can then be captured and later analysed.
This is what my techs use at work for FA on PCAs... but YMMV with "bacteria to paramecium's".
Later...
I'm a geek and while I love the idea of USB microscoped, the cameras in them aren't all that great. It costs money to do right. I'd think that you can get a beautiful unpowered optical microscope on eBay or Cragislist. Make sure it's got 2 oculars and 3 or 4 objective lenses, with immersion. For use inside, a LED flashlight works quite well as a light source. You'd also be well advised to read up on stains. They make optical microscopy way more fun.
A successful API design takes a mixture of software design and pedagogy.
I can't comment on modern microscopes because I haven't used one in years. But whichever one you decide on, be sure to concoct a hay infusion. Get a jar full of pond water and add a handful of hay or even grass clippings. Put it aside somewhere in the garage where it can stink without bothering people too much. It will yield up the most wonderful assortment of one-celled critters for your microscopic viewing pleasure--paramecia, volvox, those wonderful beings called stentors--and lots of other great stuff besides.
I write this with appreciation for the best high school biology teacher of all time, Mr. Ford, whose hay infusion was legendary for the amazing odors that emanated from it. He would periodically add more pond water or hay. A beatific smile would come over his face, and he'd say, "Oh, yeah. That's really ripe!" In all fairness, he also taught me the virtues of meticulous notes and drawings. But I suspect most of his students remember his hay infusions. Enjoy!!
And now for the most important question: does it work under Linux? Seriously, do these USB microscopes work like webcams as described in this Googled link?
>Consider also that you need thin translucent slices if you want to view tissues
You can make a microtome out of a bolt and a nut. UNF or UNEF thread pitch is helpful
Screw nut on to end of bolt by a couple of threads.
Put sample in cavity at end.
Pour paraffin wax into cavity and let cool to hold the sample in place.
Take a razor blade, screw bolt into nut by small partial turns and slice off thin slices of your sample on to slides.
taa, daa.
--
BMO
Intel QX3
Maybe a decade ago.
Have you seen what you can get for that sort of money these days?
http://www.aliexpress.com/wholesale?SearchText=microscope&CatId=0&manual=y&SortType=price_desc&filterCat=100005627%2C190405%2C15370799&page=31
"I've got more toys than Teruhisa Kitahara."
In 2000 Edmund Scientific was purchased by Science Kit and Boreal Laboratories, a western New York based science supply company. Science Kit and Boreal Laboratories is part of a group of companies that provide science supplies to elementary, middle, and high schools as well as colleges and universities.
Edmund Scientific sells high quality beginner and student microscopes in all price ranges.
Edmund's prepared slide sets have been in their catalogs for decades. You really can't go wrong here.
My father got us a real microscope. One that used batteries for the light or we could flip the light and use the mirror. It worked great and we took care of it and it was still in working condition the last time I saw it 10 years or so ago. I am now 45 so it was a quality built one, very sturdy. Children can be taught to respect their equipment, I would say for the first little while you supervise until he understands that he needs to be careful with it. Preparing slides you should probably help him with for a good while as you need a sharp knife or scalpel to do properly unless you are just looking at liquids. But glass slides could be sharp as well.
You know, some days I can hardly remember a name to save my life.
But things like this I will never, ever forget.
And hopefully, some day, I may even get to use it.
I can see the fnords!
Sounds like you want a microscope and want him to get the experience of getting to look through Dads cool microscope. Not that there is anything wrong with that, but it justifies a better toy since you aren't woried about him playing with it on his own and destroying it. If that were the case, I would say get a $30 toy...
I bought a cheap "celestron" with webcam. The camera mount came apart when I put it together. I returned it tot he store, the second one had a broken camera. It was a $30 toy.
So my wife, seeing my dissapointment, went out and got me a binocular AmScope. She went all out and spent way too much, close to $600 (what exactly do you say to "baby you can't be mad about how much I spent on your birthday gift"?), but, looking now, they have binocular models starting at about $200.
Its a solid microscope, and is officially the best one I have ever gotten to actually touch. The manual is in pretty amusing Engrish, with no copyright or company name. Its clearly meant to go right into a lab in the hands of people who already know how to use it, and the manual just a formality because you have to put something around the technical diagram of how it all fits together.
"I opened my eyes, and everything went dark again"
I would patent it if it wasn't in the Tasco microscope manual I had as a kid.
--
BMO - passin' on knowledge through the generations.
I got a reasonably decent scope when I was around 7. It was great. Cheap scopes on the other hand are just not worth the bother, they'll barely work and nothing loses kid's interest faster than some cranky finicky thing that won't produce interesting results even if you do fiddle with it for an hour. There's really just no reason to skimp that much either when decent stuff can be had for a couple bills and the cheap worthless junk is still just about the same price.
God, the smell of Canada balsam still takes me back to my youth :)
"Malo periculosam, libertatem quam quietam servitutem." -- Jefferson
Usually, that means inexpensive and military grade toughness. Two things rarely found in a precision optic :D
However, depending on your budget, you have a lot of options. First, some clarification.
You mentioned stereo being a plus. This can mean two things. Stereo objective, or stereo eyepieces. Stereo objectives are
typically found on lower power scopes used for close up work on things like circuit boards, coins, stamps, gems, jewelery, insects, etc.
Stereo eyepieces ( binocs ) are can be found on both low and high power ( compound ) scopes and are typically an upgrade ( read that, more $$$ )
Considering the age of your interested viewer, you probably want to start on the low end and work your way up if they continue to express
an interest in the field as the years go by. The internet has many sites that sell scopes, some of which I would consider to be in the budget
range for the average seven year old. Some I've used in the past: ( in no particular order )
http://www.microscope.com
http://www.microscopenet.com
http://www.microscopeuniverse.com
Even Amazon and Ebay would probably be valid places to look.
Prices are typically dictated by type, options and manufacturer.
That said, consider the following:
The low end high power setups are going to start around $100 USD for monocular ( single eyepiece ) systems with a 1D stage ( It only moves
up and down ) and LED light source. Probably what you're going to want to look at for a starter scope.
Mid range will get into Binoc ( dual ) eyepieces, better light sources ( variable halogen ), better / more objectives and a multi-dimensional stage.
( stage movement up / down, slide movement forward / back / side )
High end simply builds on the mid range with better quality components and glass.
For a seven year old ? I would start with something along these lines:
http://www.microscope.com/best-seller-omano-om116l-school-microscope-p-741.html
http://www.microscopenet.com/monocular-compound-microscope-40x400x-with-tungsten-light-p-99.html
http://www.microscope.com/omano-omtm-85-monocular-teaching-compound-microscope.html
or, if you really want the binocs, maybe something like this:
http://www.microscope.com/omano-om118-b4-compound-microscope.html
http://www.microscopenet.com/binocular-compound-microscope40x1000x-light-p-415.html
It's certainly an interesting hobby. I have a pair of scopes ( low power and a compound ) on my desk here at home I use to look at whatever
strikes my fancy. Personally, I would rather have the physical scope vs the USB. That's just a personal preference though.
I doubt there have been many technology advances so the advice is probably still current, but it will be interesting if there are.
I have a boom microscope that I use for electronics work which is very popular with my kids for looking at bugs, etc. I got mine from amscope.com for something like $350.
I also have a biological style microscope which is higher power and lit from below. My kids didn't seem to have as much interest in this. Generally, one cell looks pretty much like another unless you really know what you're looking for.
I would patent it if it wasn't in the Tasco microscope manual I had as a kid.
--
BMO - passin' on knowledge through the generations.
nothings stopping you, just put a "view the image with a computer" to the end.
on the sidenote, what's a good usb microscope?
world was created 5 seconds before this post as it is.
>nothings stopping you, just put a "view the image with a computer" to the end.
Sigh, probably true.
>on the sidenote, what's a good usb microscope?
Don't know. Never tried one.
And after looking for 10 minutes, "How much do you want to spend?"
There are toys all the way up to industrial quality.
--
BMO
Get a decent microscope. "Child friendly" means "not frustrating" -- good light, smooth focus, good light, real optics, and good light. Mechanical stage for bonus points, because little fingers have a hard time moving the slide around in tiny increments.
Stereo vision isn't a big deal, but with a child of 7, I *strongly* suggest getting a "dual head" microscope. This is designed for teaching, the student has one viewing tube, and the other viewing tube can be used by the teacher or the eyepiece of the second tube can be replaced with a standard microscope video camera eyepiece. That way a parent can help with focusing, which is tricky for kids to learn. You can also talk about what they are seeing and give them a guided tour.
Remember that real optics will give a much, much sharper view than any USB microscope or video eyepiece, so adjust expectations accordingly, but we've found that it is a much more fun family activity when the microscope is set up with video in the second tube so that everyone can see and talk about the video while taking turns looking at the eye-poppingly sharp view through the optic path.
We bought our home microscope here:
http://www.hometrainingtools.com/microscopes/c/10/
they seem to have decent prices on nicer microscopes.
That's crazy expensive. When Intel got out of the USB microscope business, I picked up 2 for $60.
http://hardware.slashdot.org/story/02/04/21/1719259/diy-computer-video-microscopy-for-under-50
Awesome furniture, accessories and cabinetry in Santa Rosa, CA: http://humanity-home.com/
American Science and Surplus has a nice collection of used microscopes (and lots of other very cool stuff) at very low prices. Their inventory changes frequently.
Celestron makes a $50 webcam-like (USB) eyepiece camera for telescopes, but it works nicely with microscopes as well. Celestron also sells inexpensive mechanical microscopes.
For thin specimens or slices, you want a compound microscope. For stereo images, you need a stereomicroscope (a.k.a. dissecting microscope). The two have very different designs. The stereomicroscope has two identical objective lenses next to each other, like the two lenses in a stereo digital camera. Unless you need very high magnifications, you can do pretty well with any of the "toy" USB devices that has a built-in webcam and a single magnifier lens (e.g. RadioShack zOrb for ca. $40).
You can build your own compound microscope, which might make a great project for a 7-year-old: http://www.funsci.com/fun3_en/ucomp1/ucomp1.htm
Finally, you can make a Leeuwenhoek microscope (the original microscope design, from the 1600s) with a single spherical lens of 2-3mm diameter and some ordindary household materials. You can make the lens if you have a torch or Bunsen burner, or get one from Edmund Optics (edmundoptics.com). Lots of how-to sites on the web, e.g. http://bizarrelabs.com/micro.htm (one design on this site uses a drop of water as the lens).
Sounds like a fun project.
I had the same quandary not too long ago. In the end, I decided to start small and work up. On ebay you can find cheap 60x and 100x pocket scopes which are a good starting point. The resolution and quality sucks, most come with led lights, some come with UV lights, however it is a very good starting point being portable and cheap.
You have a sick, twisted mind. Please subscribe me to your newsletter.
It has a USB ocular which Linux recognised straight away. Feels nice and solid, with only a tiny bit of hysteresis on the adjustment knob. Nothing a child couldn't cope with.
Optics are surprisingly good quality and the light sources use a little mains adapter, which is included. No batteries required!
There are also a few sample slides included with the microscope, but Bresser sells stained slide kits separately, these might be worth exploring, not sure.
Anyway, check the reviews, I thought it was a terrific microscope for a kid.
bundaegi is good for you
Don't they still sell the Tasco microscope kits they had when I was a kid?
I had one; it was a fairly decent microscope, and it came with slides, example specimens, cover slips and other stuff you need to mount and observe your own samples. It came with a manual explaining how to look at random things you might find in nature.
I'll be sad if you can't get these anymore! They were fairly well-made, too; real metal construction, the focus control was nicely damped and greased, etc.
It's not very good at sharpening a band saw. I tried. It was strangely satisfying though.
If I can get a few more donated, I'd like to try them as baking cookie sheets, shooting target backstops, and trebuchet ammunition.
Hurry up kids, send your donations, the trebuchet is almost done. The neighbors are starting to complain, so we'll have to do it soon. Maybe I shouldn't have been test firing it with neighborhood cats, free-roaming children, and random yard sale items. It's all for science, they should stop complaining.
Serious? Seriousness is well above my pay grade.
The sort of cheapy scope I had was great, as long as I used my desktop lamp instead of the built in light source which was way too weak.
I'd make a joke about maxing out the credit card here, but even the most expensive ones I see there are pretty reasonable.The monocular ones are in the double digits for the same magnifications I'm seeing in the binocular ones in the triple digits. I guess it really comes down to what I... I mean you... are looking to spend!
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Yeah, the one I had didn't even HAVE a built-in light. Still worked reasonably well. Something like this would probably be a good bet:
http://www.ebay.com/itm/Vintage-Leica-E-Leitz-Wetzlar-Lab-Microscope-with-Wood-Case-/320918955069?pt=LH_DefaultDomain_0&hash=item4ab842a43d
Everything you basically need, good optics. You'll need a light, but honestly a desk clamp and a decent LED light will do fine. Not too pricey and you can get good results without too much fiddling. Should be fairly rugged too.
"Malo periculosam, libertatem quam quietam servitutem." -- Jefferson
You won't be able to see bacteria without a 400x - 1000x objective.
Perhaps you can cultivate a sense of DIY by showing how you can make a microscope using an optical mouse.
I got one as a child. Seems they have a few new models now. I'm not sure if they ship to the US. http://www.kosmos.de/kosmos/wrs/wrs.nsf?openDatabase&_id=4002051636029&_lang=DE http://www.kosmos.de/kosmos/wrs/wrs.nsf?openDatabase&_id=4002051635213&_lang=DE http://www.kosmos.de/kosmos/wrs/wrs.nsf?openDatabase&_id=4002051635718&_lang=DE
Yeah, a light source and good optics go a long way
Also, good sample preparation is essential. I guess most of the problems are there.
For a light source, forget about the "built in" methods. Even a desk lamp goes a long way. And if you try different positions you can get great results, or even go for reflected light instead of transmitted light (depending on the sample)
how long until
Hi,
there are many proffessional microscopes availible on ebay, and they come at a very reasonable price too, .. if USB-Scope.price > 30 US$ then don't take it.
- USB--Scopes: forget the USB-Trash
You can get laboratory grade equitment there for arround 100 US$, binoculars and microscopes as well.
btw.
You are operating it ? -> Try it the other way arround, he will learn more quickly from his OWN mistakes, rather than from yours.
You are just a supervisor(to prevent dead serious injuries of course), adviser and the nurse, the guy with the band aid, when he broke the glass and cut himself, and the one whom later says "told you so". Except, he will remember the pain and will likely not do so again.
Minneapolis I would gladly loan you one, plus slides, cover slips and preserved specimens. Is a well cared for college lab scope. A beautiful old Nikon oil immersion. Just reply to this and we can get in contact.
Slashdot, where armchair scientists get shouted down and armchair theologians get modded up.
Made by Russian company Lomo (that also makes good amateur-grade telescopes): tough, cheap, with decent optics and lighting.
There's also a cheaper version called Yunnat (Young Naturalist), but that's a bit weak.
Oh yeah, I still have the desk lamp, lol, though the 'scope itself finally did succumb to curious children with small tools... lol. I can remember all sorts of tricks to lighting. Well slides are a great idea. You can also get plastic cover slips, which are probably not a bad idea for kids, though I'm sure they are generally inferior. Even with my bad childish sample prep though we managed to make some pretty interesting observations. Helps to have a set of prepared slides though. Damn it was fun being a kid around our place.
"Malo periculosam, libertatem quam quietam servitutem." -- Jefferson
QX3 and even the QX5 are ancient hardware. Both are out of production. I can run the QX3 in WIN7x64 using Windows Virtual PC, but just barely. If old hardware has no WIN7 USB driver, you are mostly out of luck unless you resort to OS emulation. $149 is a crazy price. These are cheap.
Sorry, but gray text on gray background is making my eyes bleed.
I bought one of these for my niece:
http://www.hometrainingtools.com/kids-led-portable-microscope/p/MI-1100LED/
I was very impressed with the quality. I would also recommend a prepared slide kit and
a slide making kit.
"We can't solve problems by using the same kind of thinking we used when we created them." -- Albert Einstein
Buying a used but well maintained lab microscope gives you solid optics, stability and motivation to use. If it's kept in a visible place, it'll trigger the want to use it.
Second that. "Child friendly" in this case means "cheap enough that if he breaks it it won't be a big deal." I had a cheap plastic "kids" microscope when I was a kid from Fischer price or something like that. It was less useful than a magnifying glass. I used it as a toy gun mostly. That didn't deter me from it: I'm a cell biologist today, but I would have loved a real microscope.
This dissecting microscope looks pretty cool.
I woudn't rule out compound scopes though. If he's interested in paramecia and bacteria, microbes, he's interested in plenty of things that are going to be visible with a compound microscope. A drop of pond water, you can generally see more with the compound scope than you can with the dissecting scope.
Also, somewhat unrelated, show him this virtual microscope and Nikon small world galleries.
How well does that work?
I also wonder if there's a way one could do cryosection like this. Freeze a sample in some solution of water and corn syrup such that it would be possible to section it like that.
>How well does that work?
It works as well as you can expect. After a couple of full turns, the sample gets loose and you have to reheat it and reseat it. It's not a lab quality microtome, but then it costs only a few cents, maximum.
But for what it is, it works surprisingly well. You can use a jam nut behind the sample holding nut to better control the turn friction.
Freeze a sample in some solution of water and corn syrup such that it would be possible to section it like that.
Freezing tends to make cells burst open from ice crystals, doesn't it?
--
BMO
http://www.chiff.com/toys/eyeclops.htm
For kids, this is the right one.
- easy to hold
- no small parts
- looks funny
- usb
I think any microscope should work for children. You just need to make sure you slice the children thin enough to fit between the glass slide plates.
Don't worry, kids are pretty tech savvy these days. Just get him an electron microscope and he'll be able to figure it out in a jiffy. Plus he'll think you're the best dad ever!
I got my kids the http://www.magiscope.com/ when they were that age. Has a cool light tube to direct light instead of a mirror or light bulb. Has a nice gear-less mechanism for adjusting focus. Uses easy to find threaded objective lenses. Pretty much indestructible..
"The ant burning ones are called magnifying glasses."
Any lens, including microscopes and telescopes, can work in much the same manner.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
I suggest a different and much cheaper initial approach: a virtual microscope. Companies like Aperio have created digital slide scanners with freeware web viewers. Many labs and universities use these scanners to create educational virtual slide banks. Do a web search for "virtual slidebox" and follow the links to thousands of diagnostic quality microscopy slides, often with explanations of what to look for. As for a true microscope for home use, I would stay away from light microscopes. Economical + kid friendly = lousy optics, low quality light path, and scarcity of things to look at. You're much better off with a dissecting microscope (aka stereo microscope). No need to rely on availability of interesting slides, and kids have a lot more fun looking up close at 3D objects.
Ebay has inexpensive stereo microscopes resembling this one: http://www.ebay.com/itm/20x-Stereo-Microscope-for-Gem-Coin-Stamp-PCB-Hair-/140757697961?pt=LH_DefaultDomain_203&hash=item20c5d005a9 I have a similar one that I got new for around $40. The magnification is a modest 50x, and it has fairly short focus length and depth but it serves well for electronic and mechanical repair and minor surgeries (splinters, hang nails)
Freezing tends to make cells burst open from ice crystals, doesn't it?
A 15% sucrose slurry acts as a cryoprotectant to prevent this. At least in the chicken embryos I work with.
We got this one and are pretty happy with it:
http://www.amazon.com/My-First-Lab-Duo-Scope-Microscope/dp/B000NOU54O
It's not stereo, but is well-made and inexpensive. Definitely a cut above a mere toy. My kids don't use it often, but we've had it a couple years and they still pull it out occasionally when they have something to look at. I would say 7yo is old enough to start operating this kind of microscope too rather than just viewing (isn't he really going to want to do that anyway?), so something inexpensive like this makes a lot of sense.
Probably every microscope buyer / seller pair since Leeuwenhoek has been having essentially the same conversation. We have that conversation at work every couple of years.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
I was about his age when I got my first microscope and a few years later a chem set. Made out of bakelite from the 1940s or 1950s the light source was from a mirror below. Don't go and by the best. You won't get so mad if something happens to it. Get one with a light. Mine was missing slides and had none of the tools with it. I got very resourceful. A local hobby shop had stuff. Expensive though. No internet back then.
Being the scientist that I am today I can fast forward you a bit. You can put two standard slides together and look at stuff and it's totally reusable. Sometimes tough to separate though and easy to break. Be patient, they will separate. When he gets a bit older you can get the slides that are disposeable. That's for the top wet-mount slide. Just run under the faucet and it's down the drain. The glass breaks up and goes away. Very fine glass. I didn't get to those until I was in college.
Try taking it to different places. Local water runoff. Try a stream, pond. Then go to the sea or one of the great lakes. You never know what you'll find.
I have a usb microscope. I'm tempted to put it on ebay. I haven't used it in years.