The objective of this study was to examine in what ways and to what extent preschoolers (5-6 years of age) manifest early Engineering Habits of Mind (EHoM) while engaging in an open-ended problem-solving construction task. The study comprised 228 children (120 boys and 108 girls). The study implemented a quantitative approach. The main research tool was an open-ended LEGO problem-solving play-like construction task (bridge building). All participants and their problem-solving processes were video-recorded. Micro-analysis of videos was conducted using a detailed coding scheme. The results of this study revealed evidence of all six EHoM during participants' execution of the open-ended Bridge Task. Most EHoM were performed by participants to a medium-low extent, based on the coding scheme. Significant positive correlations were found among five EHoM measures: "systems thinking," "problem-finding," "creative problem-solving," "visualizing," and "improving." The children's scores on the "adapting" measure did not correlate with any of the other EHoM measures. Significant correlations were found between four of the EHoM and the three measures of the quality of the construction product ("length," "height," "stability") and the "time-on-task." To conclude, young children demonstrate nascent EHoM with great enthusiasm. They invent, design, construct, and evaluate like young engineers.