You could do a lot of cooking--and make odd-sized batches (double batch, triple batch, batch-and-a-half, three-quarters of a batch, etc.) Make a pound cake (pound each of butter, flour, eggs, milk, and sugar). Split it into cupcake tins instead of a big pan; how much of each ingredient is in each cupcake? Eat the results!

For some variety, get a kitchen scale and some recipes from online or the library that use weight rather than volume for the dry ingredients.

Go to the grocery store and calculate the total volume or weight of various items in your cart. Find something you love in the bulk section; measure out various quantities of that; buy it; take it home and have a treat!

Go shopping; look at any measurements indicated and play with the conversions. (Like those 225-thread count sheets--how many threads per sheet, if twin size is so many feet wide, double is whatever, queen is whatever? how many threads if the sheet were one mile wide for a giant??)

Get out a local road atlas, pick a fun destination, and calculate your driving distance in various units; break the trips down into shorter segments, measuring each segment in different units, and then convert them all back again. Go on the trip!

Go to a home improvement store. Look at a can of house paint and note the coverage area on the label. Measure your walls, calculate area. How many cans of paint would you need? If you added one x-wide stripe of a different colour to each wall, by how much have you reduced the area of the original colour, and therefore how much less paint of the first colour do you need? Ditto for packages of floor tile, rolls of wallpaper, etc.

Go to a garden centre. Look at the germination percentages and number of seeds listed on each packet. Calculate average yield for each package of seeds (some won't tell you things like this, but some do--corn, for instance, usually says how many cobs per plant you will get; seed potatoes often tell you how many pounds to expect from each package). Assume a standard yield for each plant (and no losses to weather, weeds, insects, deer, etc.!); what is the total potential weight of vegetables you're holding in your hand? Take some seeds home; plant them!

peace
minnie