No.
You could make more than 1 text box, however.
Scratch On!
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Im thinking of something else... Scratch that
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Yeah, this seems to be a limitation of the Paint graphics editor in Scratch. What I've been doing is making sprites of text and adding and showing as needed.
If you want to create images with different sized and colored in text in them, you can download and learn to use the free Gimp software. You can download Gimp for free online (google "gimp") and that should allow you to import your image and add different text boxes.
Good luck!
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You can also just create the other text sprite in the Paint program as its own sprite or costume. No need to export. It's still pretty primitive though, so using Gimp or KidPix or any other graphics program and exporting as .jpg is a good alternative when you want to go to the next level.
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