My cooperating teacher put together these math boxes which contain 20 math cubes (10 in each color), 20 counters, dice, and cards numbered 1 – 20. Our first graders use them daily and often use laminated cards as well to build ten frames or part-part-whole models. (She also has place value cards which we have not needed to use yet). The standards these first graders are expected to meet are challenging, and new concepts are often presented before they have had time to automatize the previous ones. Using these manipulatives and tools has really enabled these six and seven year olds to develop a true number sense and have reference points for how to begin when concepts stretch their thinking.
I especially see the power of the students’ visually representing math and being able to move numbers themselves to show the action happening within equations through watching the growth of a student who transferred into the class mid-year. This student had a lot of facts memorized, but we soon realized a deep understanding of the part-part-whole model and the equal sign meaning “the same as” was lacking. Just this week, as we looked at addition and subtraction fact families, this student went from having no idea how to write the subtraction sentences when written in part=whole-part order to being able to build models of the fact families on a board and then transfer the parts and whole into subtraction number sentences.
These tools will definitely be used in my classroom next year!
uncommonteacher 
It is useful that these tools are all contained in a closed case – especially for younger grades. Using manipulatives is a great way for the younger grades to experience math through the other senses. Your CT has created an environment where they are encouraged and used regularly. I’ve talked to other cohort members whose teachers do not used manipulatives very often as they are afraid students will play with them and that they will become a distraction versus a learning tool. Students are so kinesthetic at the younger grades though. I find our third graders still want to hold the tools and use them regularly as a way to relate to the subject and more deeply understand the concept. I agree with you, that is a great tool kit for a classroom.
The boxes come from Lakeshore Learning and seem easy enough to open for the first graders and yet never seem to accidentally come open. She did a great job at the beginning of the year of letting them explore everything in the box for a few minutes, then explaining what everything is, and then giving the expectation that they are to use for math not for toys. She has bins of extras that students can play with during choice time at the end of the day. We also like that we can easily see what the students are thinking / building / doing with the manipulatives as we walk around the room.