On a more serious not, how about these

• Creating random art using the html canvas
• Creating random logos using html canvas
• Make googly-eyes tracking the mouse pointer
• Use math and html canvas for animating lines, dot, squares
• Learn the dev.to api developers.forem.com/api
• using Leaflet.js leafletjs.com/SlavaUkraini/example... to show information on maps
  • Find data for presenting like earth quake frequency
  • Meteorological data like rainfall or wind
  • Traffic data on a given date
• Using Google js charts library (developers.google.com/chart) or other chart js libraries for visualizing data
• Visualize math formulars as graphs with sliders for changing formular parameters