This dissertation examines the manner in which young school-age children construct quantitative mental imagery and act upon these constructions for arithmetic ends. After conducting dyadic teaching experiments with three first grade students who were participating in mathematics intervention, I found the connection between the participants' constructed image and the different mathematical tools varied in a manner suggestive of a progression. Additionally, I explored the interactive patterns of the intervention dyad, and identified distinct themes in which the participants' imagery constructions may be situated. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]