Congratulations to Sarah Pearson, who worked out that

Rejoice heartily, your teacher has measles (Music)

is a way of remembering the spelling of RHYTHM.

No one got the others, which were, admittedly, harder:

LADPOCS (Geography)

is a list of factors affecting the weather: latitude, altitude, distance from the sea, prevailing winds, ocean currents, clouds and rainfall, slope of the land.

BODMAS (Maths)

This is the order of working out a mathematical expression: brackets, of, division and multiplication, addition and subtraction. In other words, if you have to work out 2(4×6+2), then you first multiply 4 by 6 (=24), then add 2 (=26), then multiply the whole thing by 2 (=52). Which doesn’t seem to be in the order of BODMAS, but it made sense at the time!

King Henry’s daughter makes delicious cream meringues (Maths)

This one I’m sure of: kilometres, hectometres, decametres, metres, decimetres, centimetres, millimetres.

“But Miss, what if it’s grams and not metres?

Then it’s: King Henry’s daughter gnaws delicious cream meringues.