To teach early number sense, one of the resources Cathy uses is a Math Rack. Or should I say math racks as she uses three different ones, starting from the 5-bead rack, moving up to 10, then 20-bead rack.
Following is her Math Rack Progression:
- quick images on part/whole
- quick images of right side only, privileging the 5 structure
- combinations that make 10
- showing part, determining what's hidden
- quick image doubles, starting with 5 + 5 as a helper, privileging the 5/10 structure
- quick images doubles +/-
- making tens
- easy ones and hard ones
- one addend shown, imaging the other
- minuend shown, imaging the subtrahend
- just written problems, imaging the rack
Each participant also left the session with a 20-bead rack. Since I wanted to start my class with a review of the 5 and 10 bead racks, I had some locally made. My sister Sonia had purchased a beaded car seat some time ago, so my mom took it apart for me. Since I had taken a picture of the racks Cathy used for her demonstration. I showed it to our mechanic and in short order he created 5 and 10 bead racks for me as well as rods for the 20 bead racks. I took the rods over to our carpenter shop and tada! I had 20-bead racks.
Thanks Sonia, mom, Darren and Don for your contributions. To quote a character in one of Cathy Fosnot's books, "A real community project!"
After a few 5-10 minute session, my kindergarten students are getting to be quite proficient with the combinations of 5. My grade ones are using to 10-Bead rack to learn facts of 10 and my third graders are working on facts beyond 10 with the 20-bead rack. All told, I find the Math Racks to be very useful tools indeed!