I'm sorry Susan, but I have never seen anything like this. Perhaps from other worksheets you assume these are tens and ones? The T could stand for "Total", could it not? And are those tally marks, or could they be tens (rods) from a manipulative set? It looks like the squares (100's or flats in manipulatives)have half of them shaded.
I'm afraid that I have more questions than answers!!
Is there anyone else out there that has seen these and can interpret their meaning, or tell us how you have transcribed them? Please feel free to post any helpful suggestions.