Sure, here’s a more concise version:

In my Chapter One project, I used ArcGIS Online to map walking times and ranges for schools in Washington, DC. Using available data and basic tools, I created an easy-to-understand map. This project helped me get familiar with the toolbars, contents, and settings, allowing me to change base layers, school building symbology, and apply a colour gradient for walking times.

The colour gradient feature can also be useful in environmental contexts, like showing pollution levels from oil spills along a pipeline. I used the attribute table to adjust symbols and colours to create this gradient.