Ye Jingchen was very satisfied with the results of the teaching evaluation.

Leaving aside other disciplines, just considering mathematics, although the mathematics he learned in his previous life may not have been more profound than that of this era, the wisdom of his ancestors over thousands of years has simplified the teaching methods of mathematics, making it easier to learn.

Ye Jingshu's Fengming Academy is now teaching modern mathematics. Once her academy gains enough prestige through this innovative teaching method, it can be promoted to benefit the entire Dayuan.

The materials used to make the topographic map were common sand, soil, stones, and wood, along with some auxiliary tools brought by Xie Chang'an. Although common, they were essential to daily life, each with its own characteristics and function.

Ye Jingning was particularly interested in the copper calipers that Xie Chang'an used for measuring. He crept up next to Xie Chang'an and tried to take them several times when Xie Chang'an wasn't paying attention, but Xie Chang'an always took them first. He never succeeded.

But he was a persistent child. If it didn't work the first time, he would try twice; if it didn't work the second time, he would try three times. In short, he was determined to fight the ruler the whole time, and he never gave up despite repeated failures.

When Xie Chang'an was studying at Wenhua Hall, he didn't like to talk to people and basically didn't take the initiative to communicate with anyone except Ye Jingchen and Ye Jinghe. Yun Shu was an exception because his enthusiastic, proactive and outgoing personality was something that even Xie Chang'an found hard to handle.

After a period of time away from the Wenhua Hall, when we met again, he seemed even more aloof and unapproachable.

Fortunately, the people in the Wenhua Hall were used to his cold face, and they didn't bother each other.

He worked on the sand table with a cold expression, while Ye Jingchen followed his movements, explaining to the kids how the corresponding terrain was formed, what its characteristics were, and what combat methods should be used. Although they did not communicate in any group chat throughout the process, there was a tacit understanding between them.

Although Xie Chang'an seemed very focused, he was actually multitasking.

He really liked Ye Jingchen's way of teaching the kids, and it also showed Ye Jingchen's erudition.

Although he may not be an expert, he really seems to know a little about everything.

He became increasingly curious about the way Ye Jingchen had come from.

In that world, are there many people like Ye Jingchen, or is he unique?

Ye Jinghe was also very busy. While listening to his brother's explanation, he kept an eye on Xie Chang'an's hands, openly learning from him.

After Xie Chang'an finished setting up a sand table, Ye Jinghe felt that he had also learned how to do it.

Of course, he can't do the most crucial step of drawing a topographic map yet.

He felt he could do something as simple as setting up a sand table with a topographical map.

"Brother, can I try it?" Ye Jinghe asked Ye Jingchen as Xie Chang'an prepared to set up the second sand table.

"Of course you can. Anyone else who wants to try can join in," Ye Jingchen asked the other kids.

Ye Jinghe's gaze toward Ye Jingchen suddenly held a hint of resentment.

He only wanted to try it himself and didn't want anyone else to hold him back or steal his brother's attention.

“Brother, I want to try too!” Ye Jingyu said.

"Brother Crown Prince, I want to too!" Ye Jingyu was also very enthusiastic.

"Your Highness, it's me, it's me!" This was Yun Shu.

"Brother, may I give it a try?" This was Ye Jingyu.

“Brother, I think I can do it too.” This was Ye Jing’an.

"Brother, don't forget me! Don't forget me!" Ye Jingyan raised her hand.

As for Ye Jingning, he was still struggling with the copper calipers in Xie Chang'an's hand.

Ye Jingchen couldn't bear to tell him that although copper calipers were precious, the Eastern Palace also had them, and more than one.

Ye Jingyan looked thoughtful, while Gu Beichen was observing Xie Chang'an.

Therefore, Ye Jingchen assigned the relatively simple plateau terrain to Ye Jinghe and the others, which was also a good opportunity to test their ability to divide tasks and cooperate.

The first step is to calculate the scale of the topographic map and the sand table.

Ye Jingchen ordered someone to send over two identical copper calipers.

Ye Jingning's eyes widened when he saw this.

He immediately abandoned Xie Chang'an, came to Ye Jingchen's side, tugged at his sleeve, and looked at him expectantly.

"Jingning, what's wrong?" Ye Jingchen asked, pretending not to know anything.

Ye Jingning pointed to the copper calipers that Ye Jinghe was holding.

"That's called a copper caliper. It's a measuring tool that's more standardized and precise than a hemp rope," Ye Jingchen explained to him.

"I want it," Ye Jingning said.

With this ruler, it will be much easier for him to do whatever he wants!

"If you and your brothers and sisters make a sand table together, I'll give you one," Ye Jingchen stated his condition.

Ye Jingning hesitated for a moment, then nodded and walked towards Ye Jinghe and the others.

"Add Jingning as well. Remember to divide the work and cooperate with each other," Ye Jingchen reminded them.

Eight people working together to create a sand table, cooperation is especially important.

After calculating the scale, the topographic map should be drawn on the sand table according to the scale.

The sand table is already covered with a layer of sand, so you can draw on it.

With copper calipers to compare distances, this step is not difficult; the main challenge is patience.

Topographic maps of plateaus are simpler than those of mountains, forests, and lakes, but plateaus also have ravines, high mountains, swamps, and other diverse landforms.

All of these need to be restored one by one with sand.

They divided the sand table into eight identical sections, each responsible for one area, handling both measurement and construction themselves.

There are only two copper calipers, so only two people can start.

They assigned the two rulers according to age, starting with Yun Shu and Ye Jingyu.

While the two of them were taking measurements, the others were studying the materials needed for their respective areas.

With no one scrambling and everyone following instructions, their production process went smoothly.

However, it's not without its problems.

Because they were each only responsible for their own area, the length was accurately measured and there were no mistakes, but the height was the problem.

Before they started, they overlooked the height issue and did not set any reference points. As a result, they only realized when they were almost finished that the height of the areas each person was responsible for was slightly different.

If adjacent areas are not very different because they have a reference point, then the farther apart they are, the greater the difference will be.

However, this difference, when placed on a sand table, could completely represent a different terrain, so it is naturally unacceptable.

When a problem arises, there must be a way to solve it.

“Plateaus naturally have an altitude. This sand table's terrain is mainly plateau, so let’s set an altitude for the plateau. Any areas that are too low or too high should be redone,” Ye Jingyu suggested.

"Then whose standard should we use?" Ye Jinghe asked immediately.

Once a standard is set, the person setting the standard will need to make the fewest and most effortless changes.

Nobody wants to redo it!

Conflict is brewing!

Ye Jingchen secretly observed them, wanting to know how they would resolve this matter.