The National Library for virtual manipulatives provides a wealth of manipulative resources for teaching math. From kindergarten to 12th grade.: Numbers and operations, algebra, geometry, measurements as well as data analysis and probability, are all included with manipulatives for learning. All of these are valuable in teaching lessons using an overhead projector and for children to practice on their own at a computer using the applets.
The National Library for Virtual Manipulatives provides solutions for students to kinesthetically manipulate material on their own and try ideas to see what works. For example, one of the applets for fractions makes it very easy to teach third-graders their fractions because they can see and conceptualize using the computer manipulative. In past, we’ve used cups full of water to teach fractions, (and we should continue to do so) but this is much easier for the student to fool around and try ideas and make mistakes without fear. Computer manipulatives may be especially helpful for students with disabilities who are unable to manipulate around the kitchen. Students can learn about money with the money applet, and they can learn about number patterns with the number pattern applet. What is ideal about these is that students can practice them on their own as well as in class. And in case they want to get ahead or work on a project longer than the allotted time. Spinners, for example, are difficult to make, but easy to access and use on the spinners applet.
The National Council for teaching mathematics also has a number of applets and apps available for teaching math. Here you can also find a spinner applet to learn about probabilities. As you change the number of sectors on the spinner the probability of landing on a sector lessens and as you reduce the number of sectors it increases, for example. The logic of probabilities is much easier to understand with a visual and kinesthetic application such as this. There are a wealth of applet activities from factoring games to creating patterns, and manipulating geometric solids.
When using these for lesson plans it is very important that students are taught how to use the applet if they do not already figure it out on their own so that they can be successful in learning the material. These are excellent resources for every student in elementary school learning math.