Many math teachers often say "One of the greatest features of the smart board is the gallery of virtual manipulatives". I have found an online gallery that works as a whiteboard (and on chromebooks) that have these virtual manipulatives that will also work on the chromebooks. Virtual Manipulatives includes everything from virtual dice, to online spinners, tangrams, thermometers, etc. This can be a site that you can embed into a document, a Google Classroom Assignment, Google Presentation etc. and then have students complete their own inquiry based learning. There are also game boards, story boards and workmats for the students to use as backgrounds, games and templates for their work.
Game Boards (Grade 2 - Switcheroo)
Story Boards (Grade K - Numbered Path)
Workmats (Grade 7 Equation Chart)