You could go with something like the Adafruit FunHouse: https://www.adafruit.com/product/4985
WiFi, lots of built in hardware (temp + humidity, light, microphone, buzzer, buttons, LEDs, etc), and CircuitPython means you can program it with a USB cable and a plain old text editor.
More bucks than the "smallest ESP-whatever" dev board, but handy for learning.