Nowadays the demand of education is increasing around the world.
Once again we have to think about slightly different word forms with radically different meanings.
demands + of
Something is difficult or hard work (is ‘demanding’!):
- The joys and demands of motherhood are constant.
- Motherhood is sometimes hard work/difficult.
- The demands of IELTS are considerable.
- IELTS is hard work/difficult.
demand + for
People need something:
- Demand for oil field services has been very strong.
- A lot of people want or need oil field services.
- Demand for paper products softened slightly in recent weeks.
- Recently, fewer people have needed paper products.
Returning to our opening example, I think the writer is saying that people need education, not that it is difficult:
- Nowadays the demand for education is increasing around the world.