I cannot tell you how many hours youngest dd has spent through the years with our Lauri Fit-A-Fraction Circles. They are oversized foam circles cut into the normal fractions such as 1/2, 1/3 and so on. Each one is a different color. I couldn't find them anywhere online; this was the closest by Lauri that I could find.
The other fraction material that has been used over and over (but not quite as much; which would be impossible) are the rainbow fraction circles from Learning Resources. I only had the set for the overhead that I used as a classroom teacher but it didn't seem to bother the dc so I never bought a different set. For some reason the overhead ones are a bit cheaper here. Unfortunately they don't fit the Montessori material to measure degrees or percentage such as these :(. I had gotten the Montessori plates last summer when a school was closing but they won't work for me so I guess I'll be selling them. BUT these other ones will be perfect and I look forward to using them: Rainbow Fraction Rings also by Learning Resources. I'm not finding any online (I'm looking at an old LR catalog) but I found these "Measuring Rings" at Rainbow Resources (out of stock right now). Nasco has some fraction rings but I couldn't find a description telling the inside diameter of the circles so I can't recommend them. Surely a local teacher store will have a set I can use, right?
Another fraction work favorite: Hamburger Station. It's homemade and not even close to professional looking :) but the dc enjoy it. Each player has a set of the following circles: 2 brown, 1 green, 1 yellow, 1 red, 1 dark brown (and probably more that I can't remember). The 2 browns are wholes and they are the bread. The others are something like green (lettuce) is cut into 1/2; yellow (mustard) is cut into 1/3; red (ketchup) into 1/4; dark brown (meat) into 1/6 - whatever you decide. There is a spinner with the fractions on it. As they spin they build their hamburger by collecting fractions from their own set.
There are lots of hands-on ways to teach fractions, but I love how Montessori takes things through to abstraction. We never made it through the fractions album with the olders but I have it on hand for youngest dd. Here are lots of ideas for fraction manipulatives:
Search Amazon.com Toys&Games for fractions
Some Montessori fraction links:
This has pictures of some Mont fraction materials (I was so thrilled to see my blog on her favorites - Mil Gracias). How I would love to get my hands on one of those boxes with activities to use with the fraction circles :):
And totally unrelated:
I ran across this site with recipes for homemade hand lotion, etc. I use plain coconut oil for lotion, face cream, and so on (and on!) but this site looks fun to explore: