This assignment can easily be completed in Photoshop.
After you choose your images, load them into the program.
First you need to change the original color image to black and white. Go to Image, Adjustments, Hue and Saturation
Move your saturation down to zero
On the tool bar you will second paintbrush. Right click on this and use the “History Brush Tool”. This will restore the original color you want to highlight to the photo. In Photoshop, it is helpful to zoom in using ctrl+ and using smaller sized brushes.
Your finished product will look something like this!