Calculation method of two digits plus one digit (carry): you can first add the number in one digit to one digit, and then add the obtained number to the original integer ten; You can also make two numbers into a whole ten first, and then add the rest, or you can make a number into a whole ten and then add the rest.
When calculating the carry addition of two digits and two digits, we can understand it through scene diagrams and sticks. Only by understanding and mastering the method of "all decimals into one" in carry addition can we correctly calculate two-digit numbers and carry addition of two-digit numbers.
Let children observe, compare and think in active exploration, understand the similarities and differences between carry addition and non-carry addition, summarize the calculation method of two-digit plus two-digit carry addition, and cultivate the ability of preliminary analysis and generalization, independent exploration and transfer analogy. Experience the problem-solving process in specific situations, improve students' problem-solving ability and feel the close connection between mathematics and life.
Primary school mathematics literacy:
Mathematics is a subject that studies concepts such as quantity, structure, change and spatial model. By using abstract and logical reasoning, the shape and motion of objects are counted, calculated, measured and observed. Mathematicians have extended these concepts in order to express new conjectures with formulas and establish strictly deduced truths from properly selected axioms and definitions.
Mathematics (mathematics; Greek: μ α θ η μ α τ κ) comes from the western ancient Greek μθξμα(máthēma), which has the narrow and technical meaning of "mathematical research", even in its etymology. Its adjective meaning is related to study or hard work, and it can also be used to refer to mathematics.
Its apparent plural form in English and its apparent plural form in French can be traced back to Latin neutral plural, which Cicero translated from Greek plural. This Greek is used by Aristotle to refer to the concept of "everything counts". The original meaning is counting and counting technology. In ancient China, mathematics was called arithmetic, also called arithmetic, and finally changed to mathematics. If you want to learn math well, you must practice hard.