SINGAPORE - President Halimah Yacob found herself in the hot seat on Thursday (Oct 3) as she was grilled by a crowd curious about the Istana - from the insects in the garden and the guests to the rooms.

It was her first meeting with the 37 pupils of Greenwood Primary School and the questions came fast and furious.

One boy asked if there were insects at the Istana and President Halimah said "there are tons of species" and also butterflies and birds.

Another asked about the number of rooms in the Istana. Stumped, the President turned to her staff member for help and he said he would have to count the rooms just to be sure.

The response tickled the young crowd, who burst out laughing.

President Halimah was at the school to launch a series of children's books in celebration of the Istana's 150th anniversary this year. This is the first time the President's Office has commissioned children's books.

Titled Istana Open House Adventures, the three books present facts and history of the Istana through the eyes of four children.

At the school, President Halimah read an excerpt from the first book, The Hidden History Of The Istana. The other two books are The Living Memories Of The Istana and The Curious Sounds Of The Istana.

The children listened intently as President Halimah shared how the land where the Istana sits along Orchard Road was previously filled with thousands of nutmeg trees. Nutmeg was a precious spice, valuable for trade as it was worth more than gold during the 1800s, she said to the room of bright-eyed children.

The Istana was eventually built in 1869, complete with a sprawling garden. From the building, one could see as far as Johor and even Indonesia then, added the President.

Primary 5 student Veanna Lee, 11, was excited to meet the President and learn about the Istana. "I was nervous because I never met the President before. But she is nice and the storytelling session was very meaningful. It was humorous and fun," she said.

President Halimah also presented a set of the books to the school, and another set to the Ministry of Education.

The President's Office will donate a set of the books to all primary schools in Singapore. The books will also be available at major bookstores from Oct 11 at $15. The net proceeds from the book sale will be donated to the President's Challenge.

At the end of the session, President Halimah reminded the pupils to be kind to one another, especially those in need. "The important thing is that all of us can do something to help those who need it... Do it because you are a fellow human being," she said to the children.

Speaking to the media, she said: "I hope the children will bring back the stories that they read and have conversations with their families and friends and teachers. I think it is important to start a conversation about our place in Singapore, our history. That kind of conversation will encourage a greater understanding of the challenges we face."