Assess students' understanding of composing and decomposing whole numbers up to 10 by identifying and representing part–whole relationships. Include tasks such as finding all partitions of a given number, solving missing-addend problems, representing decompositions with manipulatives, number bonds, ten-frames or simple equations, and explaining or comparing strategies. Items should combine procedural skill and conceptual reasoning appropriate for Pre-K–Grade 2, using visual models and short word problems to measure fluency with numbers 0–10 and use of decomposition to support addition and subtraction within 10.