A free useful tool for drawing or marking up web pages for teaching or online presentations, is Page Marker. See the below link where to get it in the Chrome Extensions store.
Overview
Draw or highlight on any website in real time. Add text, lines, and shapes. Move, undo, or redo anything you draw.
Draw on any website, add text, add lines, and highlight! With Page Marker, you can use your mouse or touchscreen to draw on the web or on PDFs and save it to your computer. Paint, draw, and mark on any webpage or website.
Instructions:
1. Click the puzzle piece-shaped extensions icon in the top right corner of your browser. Pin the Page Marker red marker icon for ease of access.
2. Begin drawing on any webpage with your mouse or touchscreen.
3. To change the color of the marker, click on the color selecting box.
You can download the extension below:
https://chromewebstore.google.com/detail/page-marker-draw-on-web/jfiihjeimjpkpoaekpdpllpaeichkiod
