Problem
One or more graphics goes small when I type into a grid
Solution
Almost certainly pressing the return
key at the end of the word instead of space

If you have already done this go to the Grid drop down menu and select Clear cell
Then re-type the cell and press the space
bar after you have finished the word
Note that it is the 'space' that tells the computer to go and find a symbol. Pressing 'return' makes a new paragraph, so the computer has to make a new line in readiness.