WHEN it comes to Christmas, parents find themselves stuck with a simple mathematical equation.

Parents + presents = problems.

When it comes to buying Christmas presents for kids, how does one strike a balance between indulging and educating them? 'Tis, after all, the season of giving, so you understandably want to make your children happy. But spoiling them with yet another useless geegaw does not seem right either.

I recently hit upon a splendid way round this perennial dilemma. As an advance Christmas present, I bought a big-boy toy - an iPad - for my biggest boy (my husband).

The iPad was quickly appropriated by my smaller boy, four-year-old Julian. I knew it was going to happen, and it was all part of my evil plan.

Having heard so much about how the iPad, with its educational software and games, can be turned into a learning tool, I was tempted to introduce my elder son, Ju, to it.

But I was not about to give him a pricey gadget to which he could get addicted. Hence, the sorta-diabolical plan to give it to his Papa. That way, his dad would be the rightful owner, and could grant or withdraw iPad privileges, monitoring the child's usage. (Shhh, don't tell the Supportive Spouse.)

So far, my plan has worked.

Among the programs we have installed is a virtual globe (all the better for geography lessons); the National Aeronautics and Space Administration, or Nasa, app with its pictures of space, planets and rockets; a Museum of Modern Art, or Moma, abstract-expressionist exhibition app that lets you scroll through works by the likes of Jackson Pollock and Mark Rothko; and an ABC app that Julian uses to trace letters and words with his finger.

True, we have frivolous games like Smurfs' Village and Toyland Adventures, too. But Julian plays those in moderation - dutifully surrendering the iPad whenever Papa says that's enough.

That said, I am still going to get Julian his own Christmas present. Paging through a toy catalogue together with me, he quickly spotted a pair of rudimentary night-vision goggles for kids and called dibs on it.

We were reading a book on nocturnal animals, and the idea of being able to see in the dark like bushbabies and owls was particularly appealing to him.

But it is often a headache trying to second-guess what will seize and engage the modern kid.

"Can we ever stop buying toys for our kids?" moaned a friend of mine over SMS.

"Yes!" I replied. "Stop now."

But, really, who am I kidding? The sight of happy little faces as they tear off the wrapping paper and packaging on Boxing Day is a reward in itself. The trick is to set a budget and know how not to go overboard with the spending. For me, that number is rarely above $50.

Besides, lo-fi presents that require the pint-size recipient to exercise his or her creativity or logic in using them are the best.

Some I've hit upon so far: inexpensive finger puppets from Ikea's kids' department, board games like Scrabble and Monopoly; and a step-by-step book on simple baking.

At the end of the day, it is not so much what sort of presents you buy your kids, but more about how you can enjoy them with your child and how much mileage both of you can get out of them.

And, really, that goes for any present for kids you love, of any age.

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