Singapore Mathematics curriculum is not difficult. He is now in Primary 3 but completed Primary 6 Mathematics today (June 5, 2021). My job is done! It took us 4 years 8 months to complete 6 years of Primary School Mathematics contents. What a perseverance! :) We only used the Intensive Maths Drills series . This is the best Mathematics series in Singapore. I don't use textbooks. He started Primary 1 Mathematics when he was in Nursery 2 on November 17th 2016 . :) I actually spent a good 18-months to complete Primary 1 Mathematics with him. There were no test papers given for Primary 1 and 2. I would say, the toughest Mathematics is in Primary 5 , followed by Primary 3 and 6. The easiest level is in Primary 4 . Yes, he has 26x Primary 6 test papers to be completed by the end of this year. He managed to cope the Primary 6 Mathematics materials well and I would give him 8.5 out of 10 . Hopefully, by the time he is in Primary 6, it becomes 9.5 out of 10. No perfect 10 is fine. :