Given recent calls for integrating metacognitive strategy instruction in classrooms and current models of self-regulated learning that emphasize the importance of skilled metacognitive monitoring throughout the reading process (Azevedo, 2009a; de Bruin, & van Gog, 2012; Dent & Hoyle, 2015), this study investigated the effects of metacognitive strategies instruction and training in the use of confidence estimates upon fourth graders' reading achievement and calibration. Over the course of one school year, students in two sections of 4th Grade English Language Arts (ELA; N = 30) received metacognitive strategy instruction designed to support comprehension monitoring. During the final quarter of the school year, these students received explicit instruction in using confidence estimates as an additional tool for comprehension monitoring. Students in two other sections of 4th Grade ELA (N = 33), received standard reading instruction that did not emphasize metacognitive strategies instruction. All participants learned about informational text structures during the same 5-week period (N = 63), but students in the treatment group continued learning about metacognitive reading strategies and received calibration training using confidence estimates. Scores from standardized reading assessments were used to examine the impact of metacognitive strategies instruction and monitoring training upon treatment students' reading achievement in comparison to the control group. Students in the comparison group scored significantly higher (N = 30, M = 445.80, SD = 5.43) on the 3rd Grade Reading EOG than those in the metacognitive group (N = 33, M = 439.39, SD = 11.98). Regression analysis indicated that higher prior year achievement was associated with better performance on the 4th Grade EOG. Together, prior year achievement and condition accounted for 67% of the variance in 4th grade standardized test scores. Struggling readers in the treatment group demonstrated significantly greater mean achievement gains ( n = 15, M = 13.47, SD = 5.08) than those in the comparison group. Students in the treatment group became significantly less biased (i.e., more calibrated) than those in the comparison group. [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.]