Here is some worthy links to motor-shield and on how to build a simple wifi controlled toy (car for example) using NodeMCU:
https://blog.the-jedi.co.uk/2015/11/26/nodemcu-motor-shield-review/
https://blog.squix.org/2015/09/esp8266-nodemcu-motor-shield-review.html
https://github.com/squix78/esp8266-projects/blob/master/arduino-ide/wifi-car/smartcar.js
