Chart assignment
Charts to read and discuss
Read each chart, then answer its questions. Every chart shows its source and date; open it for a table of the numbers and the data to download.
Chart 1 of 2 · Food and drug safety
Which side effects are reported most for metformin?
The interactive chart needs JavaScript. The numbers are on the chart's page.
Nausea (30,587 reports) and diarrhea (28,674) are the reactions named most often in reports to the FDA, as of September 2026, that list a medicine containing metformin, including combination pills. Nausea and diarrhea are known stomach side effects of metformin; high blood sugar may describe the diabetes being treated, and lactic acidosis is a rare but serious known risk. A report is not proof the medicine caused the problem: anyone can send one, it lists every medicine the person was taking, and the same case can be reported twice. Reports that the medicine didn't work or was used differently than labeled are left out. Don't stop a medicine without talking to a doctor.
Questions to discuss
- In one sentence of your own, what does this chart show?
- Find the biggest change or difference in the chart. What might explain it?
- Who collected these numbers, and how recent are they? What else would you want to know before drawing a conclusion?
Source: U.S. Food and Drug Administration, Adverse Event Reporting System (FAERS) via openFDA (Public domain (U.S. government work); source U.S. Food and Drug Administration, openFDA) · Data as of Sep 30, 2026
Open the chart and its numbersChart 2 of 2 · Energy
Where does US electricity come from?
The interactive chart needs JavaScript. The numbers are on the chart's page.
In 2025 natural gas made 40.8% of US electricity, followed by nuclear (17.7%) and coal (16.6%). Wind made 10.5% and solar 6.7%. Solar counts only utility-scale plants, not rooftop panels, and the 2025 figures are preliminary.
How to read this chart
Each bar is one energy source's share of all the electricity made in the U.S. in a year, so the bars add up to about 100%. The bars start at zero, so a bar twice as long means twice the share. Solar counts only large power plants, not panels on rooftops.
Questions to discuss
- Which source makes the most electricity? About how many times more than the smallest bar?
- Which of these sources burn fuel and which don't? What share of electricity comes from each group?
- Why might a chart of this kind look different in your state than for the whole country?
Source: U.S. Energy Information Administration, Monthly Energy Review (Table 7.2a) (Public domain (U.S. government work)) · Data as of Dec 31, 2025
Open the chart and its numbersTeachers: make your own chart assignment, or change this one. Free, no account needed.