adjusted details of videos in readme.

Author: callieEDU

README.md

@@ -101,10 +101,13 @@ Get started with the DC Circuit Analysis curriculum module by downloading and un
 ## How-to Videos ##
 These short videos demonstrate some of the basic techniques used to simulate and measure circuits in the module. 
 
+### Building a Circuit ###
 https://user-images.githubusercontent.com/81383420/145588577-d98c4563-b41b-447c-acbb-afe0f6d70da5.mp4
 
+### Analyzing with a Multimeter ###
 https://user-images.githubusercontent.com/81383420/145589989-f7ae4a32-cab3-405d-b7e8-476e34d697b5.mp4
 
+### Demonstrating Oscilloscope Operation ###
 https://user-images.githubusercontent.com/81383420/145592175-ed68b140-f7d7-4355-85d4-a47feb8a82ec.mp4
 
 ## Suggested Prework ##