Here I am referring you to Virtual Labs and Online Labs platform. The Virtual labs and Online Labs hosts experiments in Science and Mathematics for the students from classes 9 to 12 with content aligned to N.C.E.R.T. /C.B.S.E. and some State Board Syllabus, but here I am giving link to Mathematical Activities. If you want to access Physics, Chemistry, Biology and English also after going to home page of OLabs website.
The Online Labs is based on the idea that lab experiments can be taught using the Internet, more efficiently and less expensively. The labs can also be made available to students with no access to labs or where equipment is not available owing to being scarce or costly. This helps them compete with students in better equipped schools and bridges the digital divide and geographical distances. The experiments can be accessed anytime and anywhere, overcoming the constraints on time felt when having access to the physical lab for only a short period of time.
You just need to click on given links.
CLASS-IX MATHEMATICAL ACTIVITIES
10. Area of circle
11. Properties of Parallelogram
12. Solving Simultaneous Equations
13. Least Common Multiple
12. Solving Simultaneous Equations
13. Least Common Multiple