Creative Hobbies 29 Piece Strong 1.25 Inch Donut Round Ceramic Ferrite Ring Magnets, with 3/8" Center Hole x 3/16" Thickness - Ideal for Use on Refrigerator, Whiteboard, Arts Science Project, Crafts

I used these for some school kids to learn more about magnets by doing activities with them. They worked well.

These magnets are great! They are really strong. My pictures show the North to North with me only holding one with 1 finger and I had to press down to control the magnet. I would say be careful when pulling them apart and putting them together. They can pinch you and it does not feel nice. Also, when reversing them (south to south or north to north) the reverse polarity is so strong that it will flip the magnets so they can be together again :) The magnets will distribute a small amount of the black matter onto you hands or whatever it touches if you are not careful. Only some of them do this. However, a little rinse and that problem is solved. They dry very quickly, but, I would suggest that wiping the bottom dry if you plan to just lay them out. I understand that many people know how magnets work. However, there are those who do not the little things so I am just giving the information so those people will know.

I am a mechanic and work in a shop that has a lot of air flow going through the shop all the time. My toolbox was $17,000 new, I am doing my very best to take care of it. I bought these magnets intending to use them to hold down the cover for my box. With winds as strong as they are in the summer, my nylon/polyester toolbox cover acts more like a sail and keeping it in place is always a pain. These magnets hold my cover firm in its place and without scratching the paint. They are also useful for holding papers in place. I actually have used these to hold tools onto the underside of vehicles as I work on them as well. They have proven to be extremely handy in the shop. My first 29 magnets lasted about 2 months only because the other technicians asked if they could have some. They are fragile and don’t like to be dropped onto solid surfaces. But if you can’t refrain from dropping these, $10 for 29 magnets is a great deal.

They are really strong! I used them for a magnet lab with third graders. Be careful, little fingers can get pinched. However, two of them broke and chipped.

I don’t understand the negative reviews for this product. They are exactly as described, size-wise and super strong. Perhaps too stong for use by an elementary school student. Also, most all ceramic magnets crack when they’re dropped on a hard surface. No surprise there.

center hole fits a 1/4 inch square dowel and slides well. They will stack on the dowel as a spring, floating above each other. Cheap enough to break one and show kids how a magnet itself wants to fly apart, not pull itself together. The pieces will want to flip so N meets S rather than 'heal the fracture'.

These were useful for our classroom experiment but broke easily if dropped on the floor. Good for most people but with a classroom full of 7th grade students they need to be careful.

I was looking for really strong magnets to use for my Science classes and these were perfect for our magnetism activity