Yes that's the book Elizabeth. Packed full of ideas and presented in a really friendly way. The science one is great too if her maths spills over into science - it has lots of experiments to do at home.
OK some more then
I love this stuff.
Talking about number things. Small children are fascinated with big numbers, we seem to have lots of conversations about hundreds and thousands and millions. Did you know a googol is 1 followed by 100 zeros? "I'm thinking of a number between 1 and 100" played like guess who. DS is quite interested in square and triangle numbers through laying out squares or triangles of marbles or counters, or building triangles of lego bricks etc.
Collections of small things are good for investigating numbers generally. And we have a box of loose change that the kids sometimes get out and play with - shops, sorting, counting in 2s/5s/10s, circle packing, all sorts of possibilities.
We have a (very cheap ebay) set of dice with different numbers of sides. They're interesting mathematical shapes to start with, and fun to play around with. A box of plastic 2d geometric shapes - again only a couple of quid - sorting, making patterns, tessellations, symmetry.
There's lots of stuff you can do for cheap or free. But other toys that are very mathematical are construction things like e.g. magnetix/geomag or k'nex. Some of my more geeky possessions that DS has had fun with are cuisenaire rods (1-10) and dienes blocks (thousands/hundreds/tens/units). Mostly just used for building and making patterns at the moment, but number concepts pop up all over the place.
Paper and pencil games - 0s and Xs, dots and boxes en.wikipedia.org/wiki/Dots_and_Boxes.
Measuring things. Set DS the challenge of working out if we would be able to get our sofa out through the front door yesterday - he had fun measuring both in various directions and came up with A Plan that involved turning it on its side. Recipes are good, specially if you need to double or halve quantities. But just setting them loose with a tape measure or a pair of scales can be fun.